Kohler 12TRES troubleshooting: 46 fault codes and 178 symptom-cause-remedy entries from the manufacturer's own service documentation.
Kohler 12TRES — full specs, parts & maintenance.
| Code | Meaning | Cause | Remedy |
|---|---|---|---|
| AF | Auxiliary fault input shutdown — Indicates a shutdown initiated by pushing the emergency stop switch. (TRES models only) Not used on RES models. | Check the position of the emergency stop button. (TRES models only) | |
| HE | High engine temperature shutdown — Shutdown occurs if the engine coolant temperature exceeds the maximum temperature for more than 5 seconds. This function becomes active after the engine reaches the crank disconnect speed. | Check for blocked air inlets and exhaust outlets. | |
| LOP | Low oil pressure shutdown — Shutdown occurs if a low oil pressure condition exists for more than 5 seconds. This function becomes active 30 seconds after the engine has reached crank disconnect speed (30 second inhibit). Note: The low oil pressure shutdown does not protect against low oil level. Check the oil level at the engine. | Check for leaks in the lubrication system.; Check the oil level and add oil if the level is low. | |
| OC | Overcrank shutdown — Shutdown occurs after 3 unsuccessful starting attempts. The crank cycle is set for three starting attempts of 15 seconds cranking and 15 seconds rest. | Check the fuel supply, spark plug, and battery.; Check for loose connections.; Contact an authorized distributor/dealer for service if problem continues. | |
| OC | Locked rotor — The generator set also shuts down on OC if no engine rotation is sensed during cranking. Shuts down 3 seconds after the fault is detected. | ||
| OF | Overfrequency shutdown — Shutdown occurs when the governed frequency exceeds 110% of the system’s frequency setpoint for more than 5 seconds. This function becomes active 10 seconds after engine start (10 second inhibit). | Contact an authorized distributor/dealer for service if problem continues. | |
| OS | Overspeed shutdown — Shutdown occurs if the engine speed exceeds 110% of the normal running speed for more than 0.3 seconds. | Contact an authorized distributor/dealer for service if problem continues. | |
| OU | Overvoltage shutdown — Shutdown occurs if the voltage exceeds 120% of the system nominal voltage for more than 2 seconds. | Contact an authorized distributor/dealer for service if problem continues. | |
| UF | Underfrequency shutdown — Shutdown occurs if the governed frequency falls below 54 Hz for more than 5 seconds. Shutdown also occurs if the governed frequency falls below 56.5 Hz for more than 60 seconds. This function becomes active 10 seconds after engine start. (10 second inhibit). | Reduce the load and restart the generator set.; Contact an authorized distributor/dealer for service if problem continues. | |
| UU | Undervoltage shutdown — Shutdown occurs if the voltage falls below 80% of the nominal system voltage for more than 10 seconds. | Reduce the load and restart the generator set.; Contact an authorized distributor/dealer for service if problem continues. | |
| HB | High battery voltage warning — Fault code is displayed if the engine starting battery voltage rises above 16 VDC for more than 30 seconds when the engine is running. Not operative during the engine crank cycle, this fault condition does not inhibit engine starting. The fault condition clears when the battery voltage returns to an acceptable level. | Check the battery rating and condition.; Check the battery charger operation. | |
| LB | Low battery voltage warning — Fault code is displayed if the engine starting battery voltage falls below 11 VDC for more than 30 seconds when the engine is not running. Not operative during the engine crank cycle, this fault condition does not inhibit engine starting. The fault condition clears when the battery voltage returns to an acceptable level. | Check the battery rating and condition.; Check the battery charger operation.; Charge or replace the battery. | |
| Locked rotor | The generator set also shuts down on OC if no engine rotation is sensed during cranking. Shuts down 3 seconds after the fault is detected. | ||
| F3 | Blown fuse F3, controller | Replace fuse; if fuse blows again, check circuit and components. | |
| F2 | Blown fuse F2, relay interface board (RIB) | Replace fuse. If fuse blows again, disconnect the board leads one at a time to identify the cause of the blown fuse: Lead 70A at the fuel valve; Lead IGN at the ignition module; Lead 71A at the starter relay; Leads FP and FN at the rotor. Repair or replace the component causing the blown fuse. If fuse continues to blow and the previous step did not identify the cause, check the continuity of leads FP and FN and the leads from the P14 connector. Replace any bad leads. Use a pin pusher to remove leads from the connector, if necessary. If replacing the leads does not solve the problem, replace the RIB. | |
| F2 | Blown fuse F2 (ADC-RES) | Replace fuse. If fuse blows again, disconnect the leads one at a time to identify the cause of the blown fuse: Lead 70C at the fuel valve; Lead IGN at the ignition module; Lead 71A at the starter relay; Leads FP and FN at the rotor. Repair or replace the component causing the blown fuse. If fuse continues to blow and the previous step did not identify the cause, check the continuity of leads FP and FN and the leads from the P14 connector. Replace any bad leads. Use a pin pusher to remove leads from the connector, if necessary. If replacing the leads does not solve the problem, replace the controller circuit board. | |
| F1 | Aux. winding fuse F1 blown | Check fuse F1 and replace if blown. If fuse blows again, check stator | |
| K3 | Flash relay (K3) on RIB (ADC 2100) | Check flash LED on RIB; Check fuse F2 and troubleshoot RIB | |
| K3 | Flash relay (K3) on controller board (ADC-RES) | Check fuse F2; Check flash LED1 on controller board. If LED1 indicates power to K3 but relay does not operate, replace controller circuit board | |
| HB | High battery voltage warning — Fault code is displayed if the engine starting battery voltage rises above 16 VDC for a 12 VDC system or above 30 VDC for a 24 VDC system for more than one minute when the engine is not running. This fault condition does not inhibit engine starting. The fault condition clears when the battery voltage returns to a voltage within the limits for more than 10 seconds. | High battery voltage | Check the battery rating and condition; Check the battery charger operation |
| LB | Low battery voltage warning — Fault code is displayed if the engine starting battery voltage falls below 8 VDC for a 12 VDC system or below 16 VDC for a 24 VDC system for more than one minute when the engine is not running. This fault condition does not inhibit engine starting. The fault condition clears when the battery voltage returns to a voltage within the limits for more than 10 seconds. | Low battery voltage | Check the battery rating and condition; Check the battery charger operation; Charge or replace the battery |
| AF | Auxiliary fault — Not used on these models. | ||
| HE | High engine temperature — Shutdown occurs if the engine coolant temperature exceeds the maximum temperature for more than 5 seconds. This protective becomes active after the engine reaches crank disconnect speed. | High engine temperature | Check for blocked air inlets and exhaust outlets |
| LCL | Low coolant level — Not used on air-cooled models. | ||
| LOC | Loss of coolant — Not used on air-cooled models. | ||
| LOP | Low oil pressure — Shutdown occurs if a low oil pressure condition exists for more than 5 seconds. This protective becomes active 30 seconds after the engine has reached crank disconnect speed (30 second inhibit). Note: The low oil pressure shutdown does not protect against low oil level. | Low oil pressure | Check the oil level at the engine; Check for leaks in the lubrication system; Check the oil level and add oil if the level is low; Check low oil pressure switch connections and operation; Check the oil pump and lubrication system |
| OC | Overcrank — Shutdown occurs after 3 unsuccessful starting attempts. The crank cycle is set for three starting attempts of 15 seconds cranking and 15 seconds rest. | Overcrank | Check the fuel supply valves and pressure; Check spark plug and battery; See Troubleshooting Chart, generator set cranks but does not start |
| OC | Overcrank — The generator set shuts down on an overcrank fault if no engine rotation is sensed. Shuts down after 3 seconds of cranking or 1 second after the fault is detected. | No engine rotation sensed | Check mag pickup connections and operation; Check for a locked rotor |
| OF | Overfrequency — Shutdown occurs when the governed frequency exceeds 110% of the system's frequency setpoint for more than 5 seconds. This protective becomes active 10 seconds after engine start (10 second inhibit). | Overfrequency | Check system frequency setting (parameter UU) on controller; Measure output frequency and adjust, if necessary; Check governor system condition and operation |
| OS | Overspeed — Shutdown occurs if the engine speed exceeds 115% of the normal running speed for more than 0.3 seconds. | Overspeed | Check governor settings and operation |
| OU | Overvoltage — Shutdown occurs if the voltage exceeds 120% of the system nominal voltage for more than 2 seconds. | Overvoltage | Check AC voltage; Check wiring and connections |
| UF | Underfrequency — Shutdown occurs when the governed frequency falls below 90% of the nominal system frequency for more than 5 seconds. This protective becomes active 10 seconds after engine start (10 second inhibit). | Underfrequency | Reduce the load and restart the generator set |
| UU | Undervoltage — Shutdown occurs if the voltage falls below 80% of the nominal system voltage for more than 10 seconds. | Undervoltage | Reduce the load and restart the generator set; Check wiring and connections; Check controller configuration, system voltage and frequency (parameter UU); Check AC voltage and adjust, if necessary; Replace the SCR module and test voltage again; Separately excite unit; Check stator continuity |
| SCF0 | Software Communication Fault 0 — Indicates a software or communication problem within the ADC 2100 | Software or communication problem within the ADC 2100 | Replace the controller |
| AF | Auxiliary fault — Indicates a shutdown initiated by the emergency stop switch or a tripped circuit breaker. (TRES models only) | Shutdown initiated by the emergency stop switch or a tripped circuit breaker | Check the position of the emergency stop button. (TRES models only) |
| OC | Overcrank — Locked rotor. The generator set shuts down on an overcrank fault if no engine rotation is sensed. Shuts down 3 seconds after the fault is detected. | No engine rotation sensed | Check mag pickup connections and operation; Check for a locked rotor |
| OS | Overspeed — Shutdown occurs if the engine speed exceeds 110% of the normal running speed for more than 0.3 seconds. | Overspeed | Check governor settings and operation |
| UF | Underfrequency — Shutdown occurs when the governed frequency falls below 54 Hz for more than 5 seconds. This protective becomes active 10 seconds after engine start. (10 second inhibit). | Underfrequency | Reduce the load and restart the generator set |
| SCF0 | Software Communication Fault 0 — Indicates a software or communication problem within the ADC-RES. | Software or communication problem within the ADC-RES | Replace the controller |
| OF | Overfrequency shutdown — Shutdown occurs when the governed frequency exceeds 110% of the system's frequency setpoint for more than 5 seconds. This function becomes active 10 seconds after engine start (10 second inhibit). | Contact an authorized distributor/dealer for service if problem continues. | |
| F2 | The generator set does not crank — Fuse F2 blown | Fuse F2 blown | Replace the fuse. Contact an authorized distributor/dealer for service if fuse blows repeatedly. |
| F3 | The generator set does not crank — Fuse F3 blown | Fuse F3 blown | Replace the fuse. Contact an authorized distributor/dealer for service if fuse blows repeatedly. |
| F1 | No AC output — Auxiliary winding fuse (F1) blown | Auxiliary winding fuse (F1) blown | Replace the fuse. Contact an authorized distributor/dealer for service if fuse blows repeatedly. |
| F3 | Generator set stops suddenly — Controller fuse (F3) blown | Controller fuse (F3) blown | Replace the fuse. If the fuse blows again, contact an authorized distributor/dealer. |
| F1 | Generator set stops suddenly — Auxiliary winding fuse (F1) blown | Auxiliary winding fuse (F1) blown | Replace the fuse. Contact an authorized distributor/dealer for service if fuse blows repeatedly. |
| F2 | The battery is discharged, but the charger has power and is operating. — Blown fuse. | Blown fuse. | Check the 5-amp fuse F2 (5A-T) inside the battery charger and replace if necessary. Check inline fuse F4 and replace if necessary. |
| Symptom | Cause | Remedy |
|---|---|---|
| Controller LED display is off | No power to the controller: Controller fuse (F3) is blown. | Replace the fuse. If the fuse blows again, contact an authorized distributor/dealer. |
| Controller LED display is off | Low or no battery voltage. | Check connections.; Check the engine starting battery and battery charger. See Figure 4-3. |
| Controller LED display is off | Generator set master switch is in the OFF/RESET position. | Move generator set master switch to the AUTO or RUN position. In AUTO, the display will not turn on until the first start command is received. |
| Controller LED display is off | The controller is in sleep mode. See Section 2.4.2. | Controller display will activate when a remote start command is received or the generator set master switch is moved to the RUN position. Use the remote switch to start generator set and activate the controller display, if desired. See Section 2.4.; Controllers with application code version 1.13 or higher can be configured to enable or disable the sleep mode. See the generator set Installation Manual for instructions. |
| The generator set does not crank. | Fault shutdown | Check for a fault code on the controller display. See Section 2.6. |
| The generator set does not crank. | Battery weak or dead | Check power to the battery charger.; Recharge or replace the battery. |
| The generator set does not crank. | Battery charger fuse blown | Replace the fuse. Contact an authorized distributor/dealer for service if fuse blows repeatedly. |
| The generator set does not crank. | Battery connections reversed or poor | Check the connections. |
| The generator set does not crank. | Fuse F2 blown | Replace the fuse. Contact an authorized distributor/dealer for service if fuse blows repeatedly. |
| The generator set does not crank. | Fuse F3 blown | Replace the fuse. Contact an authorized distributor/dealer for service if fuse blows repeatedly. |
| The generator set does not crank. | Generator set master switch in the OFF position | Move the master switch to AUTO for remote start or to RUN for local start. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically. | Air cleaner clogged | Clean and/or replace the air cleaner. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically. | Battery weak or dead | Check power to the battery charger.; Recharge or replace the battery. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically. | Battery connection poor | Clean and tighten the battery connections. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically. | Spark plug wire connection loose | Check the spark plug wires. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically. | Low oil pressure shutdown | Check the oil level. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically. | Fuel pressure insufficient | Check the fuel supply and valves. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically. | Engine malfunction | Contact an authorized distributor/dealer. |
| No AC output. | AC circuit breaker in the OFF position | Place the circuit breaker in the ON position. |
| No AC output. | AC circuit breaker tripping because of overload | Reduce the load on the generator set. |
| No AC output. | AC circuit breaker tripping because of short circuit | Contact an authorized distributor/dealer for service. |
| No AC output. | Auxiliary winding fuse (F1) blown | Replace the fuse. Contact an authorized distributor/dealer for service if fuse blows repeatedly. |
| Low output or excessive drop in voltage. | Generator set overloaded | Reduce the load. |
| Generator set stops suddenly. | Low oil pressure shutdown | Check the oil level. Check for signs of oil leaks. |
| Generator set stops suddenly. | Out of fuel | Check fuel supply. |
| Generator set stops suddenly. | Overcrank shutdown | Reset the controller. If the overcrank fault occurs again, contact an authorized distributor/dealer. |
| Generator set stops suddenly. | Controller fuse (F3) blown | Replace the fuse. If the fuse blows again, contact an authorized distributor/dealer. |
| Generator set stops suddenly. | Overspeed shutdown | Reset the controller. If the overspeed fault occurs again, contact an authorized distributor/dealer. |
| Generator set stops suddenly. | Generator set master switch in the OFF/RESET position | Move the switch to the correct position (RUN or AUTO). |
| Generator set stops suddenly. | Remote stop command received from a remote switch or ATS | Check the remote switch position. |
| Generator set stops suddenly. | Engine malfunction | Contact an authorized distributor/dealer. |
| Generator set stops suddenly. | Auxiliary winding fuse (F1) blown | Replace the fuse. Contact an authorized distributor/dealer for service if fuse blows repeatedly. |
| Red LED stays on for more than 24 hours | One or more inoperative or damaged cells. | Load test the battery and replace, if necessary |
| Red LED stays on for more than 24 hours | Battery charger has reduced its output voltage below the normal level due to a DC overload or a DC short. | Remove the source of the overload or short. Disconnect the battery charger’s black (NEGATIVE) ring terminal from the battery. Reapply AC power and the green LED only should now light. |
| Red LED stays on for more than 24 hours | Onboard DC systems are drawing more current than the battery charger can replace. | Turn off all DC equipment while charging. |
| Red and green LEDs stay on for more than 24 hours | Onboard DC systems are drawing between 1.5 and 5 amps. | Turn off all DC equipment while charging. |
| Red and green LEDs stay on for more than 24 hours | One or more inoperative or damaged cells. | Load test the battery and replace, if necessary |
| Red and green LEDs stay on for more than 24 hours | Extremely low AC voltage at the battery charger. | Apply a higher AC voltage source or reduce the length of the extension cord. |
| Green LED stays on when the battery is known to be low | Open DC output fuse. | Replace AGS-10 fuse. |
| Green LED stays on when the battery is known to be low | Faulty or contaminated terminal connections. | Clean and tighten or repair all terminal connections. |
| Green LED stays on when the battery is known to be low | One or more inoperative or damaged cells. | Load test the battery and replace, if necessary. |
| Neither of the LEDs turn on when the AC power is applied | No AC power available at the battery charger. | Connect AC power or reset the AC breaker on the main panel. |
| Neither of the LEDs turn on when the AC power is applied | Component failure. | Replace battery charger. |
| Green LED is off and there is no output voltage. | No power to the battery charger. | Check the power supply to the charger.; Check the upstream circuit breakers and fuses.; Check fuse FS (1A-T) inside the battery charger. |
| Abnormal low voltage, charger is operating. | The battery completely discharged and the charger is operating at the current limit. | Disconnect the battery and verify that the charger output is 13.2 VDC.; Reconnect the charger and allow time for the battery to recharge. The battery voltage should rise gradually.; Test the battery. |
| The battery is discharged, but the charger has power and is operating. | Blown fuse. | Check the 5-amp fuse F2 (5A-T) inside the battery charger and replace if necessary.; Check inline fuse F4 and replace if necessary. |
| Generator set does not crank | Weak or dead battery | Recharge or replace battery. If battery is weak or dead, check battery charger fuse, power supply, and operation. |
| Generator set does not crank | Battery connections | Check for reversed or poor battery connections. |
| Generator set does not crank | Open circuit in engine/controller connections | Check for loose connections. Check the wire harness continuity. |
| Generator set does not crank | Crank relay on relay interface board (ADC 2100) | Check connections to the RIB. Check for 12VDC to the RIB on lead 71N. Check for a good ground connection (lead 16N). Check crank relay K2 operation (LED3). Replace the RIB if relay does not operate. |
| Generator set does not crank | Crank relay K3 on controller circuit board (ADC-RES) | Check connections to the controller. Check for a good ground connection. Check LED3 to verify 12 VDC to relay K3. If LED3 is not lit, check for 12 VDC to the board. If LED3 is lit but the relay does not operate, replace the controller circuit board. |
| Generator set does not crank | Generator set master switch | Check connections to the master switch. Test function of master switch. |
| Generator set does not crank | Poor ground (--) connection | Clean and retighten. |
| Generator set does not crank | Starter relay | Check connections to the starter relay. Check continuity of circuit. Check that the starter relay picks up when 12VDC is applied at lead 71A connection. |
| Generator set does not crank | Starter | Check starter connections. Rebuild or replace starter. |
| Generator set does not crank | Controller | Check controller connections and operation. Check for power to the controller. Move generator set master switch to OFF/RESET and then to RUN. |
| Cranks but does not start | No fuel | Open (turn on) manual fuel valve. Check fuel supply tank (LP). |
| Cranks but does not start | Insufficient fuel pressure | Check fuel pressure to the generator set. Verify adequate fuel pressure and pipe size for the generator set plus all other gas appliances. |
| Cranks but does not start | Fuel regulator/valve | Check regulator/valve operation. |
| Cranks but does not start | Spark plugs or spark plug connections | Check spark plug wires and connections. Replace or clean and regap spark plugs. |
| Cranks but does not start | Loose connection or open circuit | Check for loose or open connection at the fuel valve (lead 70A) and at the engine spark control module (leads IGN and 70A). Check controller/engine wiring continuity. |
| Cranks but does not start | Air cleaner clogged | Clean or replace. |
| Cranks but does not start | Magnetic pickup | Check for 1.75 volts or higher from the magnetic pickup during cranking. A lower signal will cause the stepper motor to open and close during cranking. Measure the resistance across the magnetic pickup according to the procedure in Section 6.9.4. Replace the mag pickup if the resistance is more than 20% higher or lower than the specified value. |
| Cranks but does not start | Incorrect controller configuration | Check for correct controller configuration settings. |
| Cranks but does not start | Ignition system spark control or ignition coil | Test and/or replace components. |
| Cranks but does not start | Digital spark advance ignition (DSAI) connections (12kW only) | Connect for natural gas. Disconnect for LP. Check for loose connections. |
| Cranks but does not start | No engine rotation sensed (check for an overcrank fault shutdown) | Check mag pickup connections, air gap, resistance, and operation. Check for locked rotor. |
| Starts hard | Low battery voltage | Check battery voltage and battery charger connections, power supply, and operation. |
| Starts hard | Air cleaner clogged | Replace element. |
| Starts hard | Fuel mixture adjustment incorrect | Adjust fuel valve. |
| Starts hard | DSAI leads incorrectly connected or disconnected (12kW only) | Connect for natural gas. Disconnect for LP. |
| Starts hard | Spark plug(s) | Replace or regap spark plug(s). |
| Starts hard | Spark plug wire(s) | Check spark plug wires and connections. Replace spark plug wires. |
| Starts hard | Ignition components (spark control or ignition module) | Test/replace ignition components. |
| Starts hard | Insufficient fuel pressure | Check fuel pressure. |
| Starts hard | Worn piston rings, valves | Check compression. |
| Starts but shuts down | Fault shutdown | Check for a fault shutdown code on the controller’s LED display. Correct the fault and then move the generator set master switch to OFF/RESET to reset the controller. |
| Stops suddenly | Fault shutdown | Check for a fault shutdown code on the controller’s LED display. Correct the fault and then move the generator set master switch to OFF/RESET to reset the controller. |
| Stops suddenly | No fuel | Turn on fuel supply. |
| Stops suddenly | Fuel line restriction | Inspect fuel lines. |
| Stops suddenly | Fuel lines too long | Check fuel line length. |
| Stops suddenly | Air cleaner clogged | Replace element. |
| Stops suddenly | Blown fuse | Check fuses F1, F2 and F3. Replace any blown fuses. If fuse blows again, test generator components. |
| Stops suddenly | Spark plug(s) | Replace and regap plug(s). |
| Stops suddenly | Engine overheated (hot engine only) | Check air intake, fuel adjustment, oil level, air inlet/outlet. |
| Stops suddenly | Low oil pressure (LOP) switch | Attempt startup. If unit shuts down, remove lead from LOP switch and reset controller. A successful restart attempt indicates a faulty LOP shutdown switch. Note: Check engine oil pressure before performing test and/or replacing LOP shutdown switch. |
| Stops suddenly | Fuel valve/fuel regulator | Check regulator/valve operation. |
| Stops suddenly | Engine overloaded | Reduce electrical load. |
| Stops suddenly | Loss of generator output voltage to controller | Check connections at P15 plug. Check continuity of AC sensing leads 11 and 44. |
| Stops suddenly | Magnetic pickup connections | Check for loose connections to the mag pickup. |
| Stops suddenly | Ignition module | Test and/or replace. |
| Stops suddenly | K3 (flash) relay on RIB (ADC 2100) | Check for Flash LED illumination. Check fuse F2. Replace relay board. |
| Stops suddenly | K3 (flash) relay on controller board (ADC-RES) | Check for Flash LED1 illumination. Check fuse F2. If LED1 is lit but relay does not operate, replace controller board. |
| Operates erratically | Air cleaner clogged | Replace element. |
| Operates erratically | Spark plug(s) | Replace and regap plugs. |
| Operates erratically | Spark plug wire(s) | Replace spark plug wires. |
| Operates erratically | DSAI leads incorrectly connected or disconnected (12kW only) | Connect for natural gas. Disconnect for LP. |
| Operates erratically | Fuel line restriction | Check fuel lines. |
| Operates erratically | Fuel mixture adjustment incorrect | Check and/or adjust. |
| Operates erratically | Magnetic pickup connections | Check for loose connections to the mag pickup. |
| Operates erratically | Governor adjustment incorrect | Adjust governor stability. |
| Operates erratically | Ignition system | Test and/or replace components. |
| Operates erratically | Inadequate cooling (hot engine only) | Inspect air inlet and outlet. |
| Operates erratically | Carbon buildup in engine | Clean cylinder head. |
| Operates erratically | Engine valves not seating correctly | Check cylinder pressures with leakdown test. Inspect valves and valve seats. |
| Lacks power | Air intake restriction, inadequate cooling | Inspect air intakes and exhaust for obstructions. Check air cleaner. |
| Lacks power | Generator overloaded | Reduce load. |
| Lacks power | Spark plug(s) | Replace and regap plug(s). |
| Lacks power | Spark plug wire(s) | Replace spark plug wires. |
| Lacks power | DSAI leads incorrectly connected or disconnected (12kW only) | Connect for natural gas. Disconnect for LP. |
| Lacks power | Insufficient fuel pressure | Check fuel pressure at carburetor outlet. |
| Lacks power | Fuel line restriction | Check fuel pipe size. |
| Lacks power | Fuel regulator | Check function of fuel regulator. |
| Lacks power — Engine not running at rated rpm | Engine not running at rated rpm | Check controller settings for unit configuration (UC) and engine type (EC); Adjust governor speed |
| Lacks power — Engine power loss | Engine power loss | Refer to the engine service manual for troubleshooting and repair instructions |
| Lacks power — Governor malfunction or misadjustment | Governor malfunction or misadjustment | Test/readjust governor |
| Lacks power — Ignition system | Ignition system | Test and/or replace |
| Lacks power — Overheats | Inadequate cooling | Inspect cooling system for air intake obstructions |
| Lacks power — Overheats | Fuel mixture adjustment incorrect | Readjust fuel mixture. Note: Adjusting the fuel mixture may void the emission certification |
| Low output or excessive drop in voltage — Generator overloaded | Generator overloaded | Reduce load |
| Low output or excessive drop in voltage — Incorrect controller configuration | Incorrect controller configuration | Check and adjust the controller configuration parameters |
| Low output or excessive drop in voltage — Incorrect controller voltage settings | Incorrect controller voltage settings | Check and adjust the controller voltage settings |
| Low output or excessive drop in voltage — Alternator or control system | Alternator or control system | Perform separate excitation procedure to isolate problem to the alternator or the control system |
| Low output or excessive drop in voltage — SCR module | SCR module | Check wiring and connections to the SCR module; Check auxiliary winding fuse F1; Replace SCR module and test voltage |
| Low output or excessive drop in voltage — Controller | Controller | Check controller settings. Check controller fuse, wiring and connections; Before replacing controller, replace SCR module and test voltage |
| Low output or excessive drop in voltage — Rotor (open, grounded, or shorted windings) | Rotor (open, grounded, or shorted windings) | Test and/or replace |
| Low output or excessive drop in voltage — Stator (open, grounded, or shorted windings) | Stator (open, grounded, or shorted windings) | Test and/or replace |
| Low output or excessive drop in voltage — Brush connection | Brush connection | Check for loose brush connections; Check the resistance through the brushes. Resistance through the brushes should be low, 0.1--0.2 ohms without meter lead resistance |
| Low output or excessive drop in voltage — Low engine speed causing voltage roll-off | Low engine speed causing voltage roll-off | Check system voltage/frequency (Uu) and engine type (Ec) parameters; Adjust engine governor speed; Troubleshoot engine |
| Light flicker — Voltage stability (gain) setting | Voltage stability (gain) setting | Check and adjust the voltage stability (gain) setting using the controller keypad |
| High output voltage — Incorrect controller configuration | Incorrect controller configuration | Check and adjust the controller configuration parameters |
| High output voltage — Incorrect controller voltage settings | Incorrect controller voltage settings | Check and adjust the controller voltage settings |
| High output voltage — Engine speed too high | Engine speed too high | Check engine speed using tachometer or frequency meter; Adjust governor as necessary |
| High output voltage — Loose voltage sensing connections | Loose voltage sensing connections | Check connections: stator leads 11 and 44 and P15 controller connection |
| High output voltage — SCR module | SCR module | Check wiring and connections to the SCR module; Check auxiliary winding fuse F1 (lead 55); Replace SCR module and recheck voltage |
| High output voltage — Controller | Controller | Check fuses, wiring and connections. Before replacing controller, replace SCR module and test voltage |
| No output voltage — AC output circuit breaker open | AC output circuit breaker open | Check for AC voltage on the generator side of circuit breaker. If there is AC voltage on the generator side of the breaker, then a problem in the load circuits is causing the line circuit breaker to trip. Check for and correct short circuits or overloading on the load side before resetting the circuit breaker |
| No output voltage — Alternator or control system | Alternator or control system | Perform separate excitation procedure to isolate the problem to the alternator or the control system. Then troubleshoot the alternator or control system components as follows |
| No output voltage — SCR module | SCR module | Check auxiliary winding fuse F1; Replace SCR module and test voltage |
| No output voltage — Controller | Controller | Check controller settings. Check wiring and connections. Before replacing controller, replace SCR module and check voltage |
| No output voltage — Open wiring, terminal, or pin in buildup circuit or SCR module circuit | Open wiring, terminal, or pin in buildup circuit or SCR module circuit | Check continuity |
| No output voltage — Brushes | Brushes | Inspect brushes and replace if worn; Check for brushes sticking in brush holder or broken brush spring |
| No output voltage — Rotor connections | Rotor connections | Check for open circuit in rotor connection circuit (leads FN and FP to SCR and RIB) |
| No output voltage — Rotor slip rings dirty or corroded | Rotor slip rings dirty or corroded | Check slip ring condition |
| No output voltage — Rotor (open, grounded, or shorted windings) | Rotor (open, grounded, or shorted windings) | Check voltage and continuity |
| No output voltage — Stator (open, grounded, or shorted windings) | Stator (open, grounded, or shorted windings) | Check voltage and continuity |
| Noisy operation — Exhaust system leaks | Exhaust system leaks | Check and replace as necessary |
| Noisy operation — Engine not running smoothly | Engine not running smoothly | See Generator set operates erratically in this table |
| Noisy operation — Broken or damaged vibromount(s) | Broken or damaged vibromount(s) | Check and replace as necessary |
| Noisy operation — Loose or vibrating sheet metal/housing | Loose or vibrating sheet metal/housing | Retighten screws, replace rivets |
| Noisy operation — Exhaust piping or air inlets/outlets not securely installed | Exhaust piping or air inlets/outlets not securely installed | Inspect for loose parts and secure if necessary |
| Noisy operation — Excessive engine/generator vibration | Excessive engine/generator vibration | Check, rotor, crankshaft, bearing, etc. (disassembly of engine and/or alternator may be required) |
| Controller troubleshooting — Controller | Controller | Check controller settings; Adjust controller settings as required; Check for power to the controller at lead PF1; Check/replace fuse F3. Check battery; Check controller fuse F3; Replace controller fuse; Check controller wiring and connections; Tighten connections and/or replace wiring; Replace SCR module and recheck voltage; Replace the SCR module; Perform all tests listed under high output voltage; Replace the controller only if previous steps do not solve the problem |
| Controller troubleshooting — SCR module | SCR module | Check wiring and connections to the SCR module; Tighten connections and/or replace wiring to the SCR module; Test the SCR module using the procedure in Section 6.8; Replace the SCR module and recheck voltage; Check auxiliary winding fuse F1 (lead 55); Replace auxiliary winding fuse F1 (lead 55) |
| Controller LED display is off | The controller is in sleep mode. See Section 2.5.2. | Controller display will activate when a remote start command is received or the generator set master switch is moved to the RUN position. Use the remote switch to start generator set and activate the controller display, if desired. See Section 2.5.; Controllers with application code version 1.13 or higher can be configured to enable or disable the sleep mode. See the generator set Installation Manual for instructions. |
| The generator set does not crank | Fault shutdown | Check for a fault code on the controller display. See Section 2.7. |
| The generator set does not crank | Battery weak or dead | Check power to the battery charger; Recharge or replace the battery. |
| The generator set does not crank | Battery charger fuse blown | Replace the fuse. Contact an authorized distributor/dealer for service if fuse blows repeatedly. |
| The generator set does not crank | Battery connections reversed or poor | Check the connections. |
| The generator set does not crank | Generator set master switch in the OFF position | Move the master switch to AUTO for remote start or to RUN for local start. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically | Air cleaner clogged | Clean and/or replace the air cleaner. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically | Battery weak or dead | Check power to the battery charger; Recharge or replace the battery. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically | Battery connection poor | Clean and tighten the battery connections. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically | Spark plug wire connection loose | Check the spark plug wires. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically | Low oil pressure shutdown | Check the oil level. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically | Fuel pressure insufficient | Check the fuel supply and valves. |
| The generator set cranks but does not start, starts hard, lacks power, or operates erratically | Engine malfunction | Contact an authorized distributor/dealer. |
| No AC output | AC circuit breaker in the OFF position | Place the circuit breaker in the ON position. |
| No AC output | AC circuit breaker tripping because of overload | Reduce the load on the generator set. |
| No AC output | AC circuit breaker tripping because of short circuit | Contact an authorized distributor/dealer for service. |
| Low output or excessive drop in voltage | Generator set overloaded | Reduce the load. |
| Generator set stops suddenly | Low oil pressure shutdown | Check the oil level. Check for signs of oil leaks. |
| Generator set stops suddenly | Out of fuel | Check fuel supply. |
| Generator set stops suddenly | Overcrank shutdown | Reset the controller. If the overcrank fault occurs again, contact an authorized distributor/dealer. |
| Generator set stops suddenly | Overspeed shutdown | Reset the controller. If the overspeed fault occurs again, contact an authorized distributor/dealer. |
| Generator set stops suddenly | Generator set master switch in the OFF/RESET position | Move the switch to the correct position (RUN or AUTO). |
| Generator set stops suddenly | Remote stop command received from a remote switch or ATS | Check the remote switch position. |
| Generator set stops suddenly | Engine malfunction | Contact an authorized distributor/dealer. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Documented causes: Low oil pressure shutdown; Out of fuel; Overcrank shutdown; Controller fuse (F3) blown. See the table for the matching fixes.
Documented causes: Fault shutdown; No fuel; Fuel line restriction; Fuel lines too long. See the table for the matching fixes.
Documented causes: Air cleaner clogged; Battery weak or dead; Battery connection poor; Spark plug wire connection loose. See the table for the matching fixes.