The Detector 12 is a generator-set controller. It is used on generator sets from Cummins/Onan and Detector, including the 750 DFZ, DKAE, DKAF and DKAH.
Used across brands: Cummins/Onan, Detector
Also fitted to: Cummins/Onan AC–151b (9/04).
| Code | Meaning |
|---|---|
| FAULT 1 | An undedicated fault May be factory programmed as a shutdown or non-shutdown, and as a timed or non-timed (normally set for timed shutdown). |
| FAULT 2 | Same features as Fault 1 (normally set for timed shutdown). |
| HI ENG TEMP | Engine has shut down because of critically high temperature. |
| LO ENG TEMP | Engine temperature is marginally low for starting. Indicates inoperative coolant heater, (Lamp lights when engine water jacket temperature is 70°F (21 OC) or lower. Since the lamp goes out after the engine warms up there should be no cause for alarm even during initial generator set operation.) |
| LO FUEL | Fuel supply is marginally low. |
| LO OIL PRES | Engine has shut down because of critically low oil pressure. |
| OVERCRANK | Starter has been locked out because of excessive cranking time. |
| OVERSPEED | Engine has shut down because of excessive speed. |
| Symptom | Cause | Remedy |
|---|---|---|
| *12. The FAULT 1 or FAULT 2 fault lamp lights. Engine shuts down immediately, engine runs for several seconds and then shuts down, or engine continues to run. | The standard undesignated fault functions are programmed to shut down the set when a fault is sensed. Fault 1 is timed delayed while Fault 2 is immediate. The nature of the fault is an optional selection that is determined when the set installation is designed. The undesignated fault functions may also be programmed for non-shutdown or non-time delay. | |
| *13. Fault lamp lights but no fault exists. Engine gauges show oil pressure, engine temperature, and frequency (speed) are within normal limits. | The monitor board or a sensor may be at fault. Contact an Onan Dealer or Distributor for service. | |
| *14. Engine starts from generator control panel but will not start automatically or from a remote panel. | Indicates possible fault with control or starting system. a. Fault lamp on. Correct fault and reset control. b. Poor battery cable connections. Clean the battery cable terminals and tighten all connections. c. Discharged or defective battery. Recharge or replace the battery. d. Contact an Onan Dealer or Distributor for assistance if none of the above. | |
| *15. Engine will not crank. | Indicates possible fault with control or starting system. a. Fault lamp on. Correct fault and reset control. b. Poor battery cable connections. Clean the battery cable terminals and tighten all connections. c. Discharged or defective battery. Recharge or replace the battery. d. Contact an Onan Dealer or Distributor for assistance if none of the above. | |
| *16. No AC output voltage. | Field breaker is tripped. Reset breaker. Contact an Onan Dealer or Distributor if voltage build up causes breaker to trip. | |
| *6. OVERCRANK lamp lights and engine stops cranking. | Indicates possible fuel system problem. a. Check for empty fuel tank, fuel leaks, or plugged fuel lines and correct as required. b. Check for dirty fuel filter and replace if necessary (see MAINTENANCE section). c. Check for dirty or plugged air filter and replace if necessary (see MAINTENANCE section). d. Refer to Step 5. e. Reset the control and restart after correcting the problem. Contact an Onan Dealer or Distributor for service if none of the above. | |
| *7. Engine runs and then shuts down, OVERSPEED lamp lights. | Indicates engine has exceeded normal operating speed. Contact an Onan Dealer or Distributor for service. | |
| 10. LO FUEL lamp lights. Engine shuts down and LO OIL PRES lamp lights. | Indicates engine has run out of fuel. Check fuel level and replenish as required. | |
| 11. LO ENG TEMP lamp lights. Set is in standby mode but is not operating. | Indicates engine coolant heater is not operating or is not circulating coolant. Check for the following conditions: a. Coolant heater not connected to power supply. Check for blown fuse or disconnected heater cord and correct as required. b. Check for low coolant level and replenish if required. Look for possible coolant leakage points and repair as required. c. Contact an Onan Dealer or Distributor if none of the above. | |
| 17. Green RUN lamp does not light following engine start-up. | Indicates possible Start/Disconnect relay failure. Contact an Onan Dealer or Distributor for assistance. | |
| 8. SWITCH OFF lamp flashes. | Indicates Run/Stop/Remote switch is in the Stop position which will prevent automatic starting if an automatic transfer switch is used. Move the Run/Stop/Remote switch to the Remote position for automatic starting. | |
| 9. LO FUEL lamp lights. Engine continues to run. | Indicates diesel fuel supply is running low. Check fuel supply and replenish as required. | |
| Engine has overheated (engine temperature has risen above 230°F/110°C) or coolant level is low | A. Check coolant level and replenish if low. b. Check for possible coolant leakage points and repair if necessary. c. Check for obstructions to cooling airflow and correct as necessary. d. Check for a slipping fan belt and tighten if loose. e. Reset control and restart after locating and correcting problem. Contact an authorized service center if none of the above. | |
| Engine oil pressure has dropped to 20 psi (138 kPa) | If generator is powering critical loads and cannot be shut down, wait until next shutdown period and then follow step 4 procedure. | |
| Engine runs and then shuts down, OVERSPEED lamp lights | Contact an authorized service center for service. | |
| Engine runs and then shuts down, OVERSPEED lamp lights. | Indicates engine has exceeded normal operating speed. | Contact an authorized service center for service. |
| Engine starts from generator control panel but will not start automatically or from a remote panel (Note: The Run/Stop/Remote switch must be in the Remote position for automatic or remote starting) | Contact an authorized service center for service. | |
| Engine starts from generator control panel but will not start automatically or from a remote panel. | Remote circuit breaker is tripped. Reset breaker and restart. Contact an authorized service center if breaker trips after resetting. | |
| Engine will not crank | A. Fault lamp on. Correct fault and reset control. b. Poor battery cable connections. Clean the battery cable terminals and tighten all connections. c. Discharged or defective battery. Recharge or replace the battery. d. Emergency stop button is pushed in. To reset, pull switch out and move Run/Stop/Remote switch to Stop position. Then push test switch to Reset/Lamp position. e. Contact an authorized service center if none of the above. | |
| Engine will not crank. | Indicates possible fault with control or starting system. Check for the following conditions: a. Fault lamp on. Correct fault and reset control. b. Poor battery cable connections. Clean the battery cable terminals and tighten all connections. c. Discharged or defective battery. Recharge or replace the battery. d. Emergency stop button (if equipped) pushed in. To reset, pull switch out and move Run/Stop/Remote switch to Stop position. Then push test switch to Reset/Lamp position. e. Contact an authorized service center if none of the above. | |
| Fault lamp activated | Low oil pressure or high coolant temperature | Make adjustments or corrections, then restart the set |
| Fault lamp lights but no fault exists. Engine gauges show oil pressure, engine temperature, and frequency (speed) are within normal limits | The monitor board or a sensor may be at fault. Contact an authorized service center. | |
| Fault lamp lights but no fault exists. Engine gauges show oil pressure, engine temperature, and frequency (speed) are within normal limits. | The monitor board or a sensor may be at fault. Contact an authorized service center for service. | |
| Green RUN lamp does not light following engine startup | Indicates possible Start/Disconnect relay failure. Contact an authorized service center for assistance. | |
| Green RUN lamp does not light following engine startup. | Indicates possible Start/Disconnect relay failure. | Contact an authorized service center for assistance. |
| Green RUN lamp lights following engine start-up. | Indicates all engine systems are normal. No corrective action required. | |
| HI ENG TEMP lamp lights. Engine shuts down. | Indicates engine temperature has risen to approximately 220°F (104°C) or coolant level is low. If generator is powering non-critical and critical loads and cannot be shut down, use the following: a. Reduce load if possible by turning off non-critical loads. b. Check air inlets and outlets and remove any obstructions to airflow. If engine can be stopped, follow procedure in step 3. | |
| LO ENG TEMP lamp lights. Set is in standby mode but is not operating. | (Lamp lights when engine coolant temperature is 70° F (21° C) or lower. Since the lamp goes out after the engine warms up, there should be no cause for alarm even during initial generator set operation.) | |
| LO FUEL LAMP lights. Engine shuts down and LO OIL PRES lamp lights. | Indicates engine has run out of fuel. | Check fuel level and replenish as required. |
| LO FUEL lamp lights. Engine continues to run | Indicates diesel fuel supply is running low. Check fuel supply and replenish as required. | |
| LO FUEL lamp lights. Engine continues to run. | Indicates diesel fuel supply is running low. | Check fuel supply and replenish as required. |
| LO FUEL lamp lights. Engine shuts down and LO OIL PRES lamp lights | Indicates engine has run out of fuel. Check fuel level and replenish as required. | |
| LO OIL PRES lamp lights. Engine shuts down | A. Check oil level, lines and filters. b. If oil system is OK but oil level is low, replenish. c. Reset control and restart. Contact an authorized service center if oil pressure is not in the range of 29 to 65 psi (200 to 447 kPa). d. If engine can be stopped, follow procedure in Step 4. | |
| LO OIL PRES lamp lights. Engine shuts down. | Indicates engine oil pressure has dropped to 14 psi (97 kPa). | A. Check oil level, lines and filters. i. If oil system is OK but oil level is low, replenish. b. Reset control and restart. Contact an authorized service center if oil pressure is not in the range of 25 to 40 psi (172 to 275 kPa). |
| No AC output voltage | Field breaker is tripped. Reset breaker. Contact an authorized service center if voltage buildup causes breaker to trip. | |
| No AC output voltage. | Field breaker is tripped. Reset breaker. Contact an authorized service center if voltage buildup causes breaker to trip. | |
| OVERCRANK lamp lights and engine stops cranking | A. Check for fuel prime, empty fuel tank, fuel leaks, or plugged fuel lines and correct as required. b. Check for dirty fuel filter and replace if necessary (see Maintenance section). c. Check for dirty or plugged air filter and replace if necessary (see Maintenance section). d. Reset the control and restart after correcting the problem. Contact an authorized service center for service if none of the above. | |
| OVERCRANK lamp lights and engine stops cranking. | Indicates possible fuel system problem. | A. Check for empty fuel tank, fuel leaks, or plugged fuel lines and correct as required. b. Check for dirty fuel filter and replace if necessary (see Maintenance section). c. Check for dirty or plugged air filter and replace if necessary (see Maintenance section). d. Reset the control and restart after correcting the problem. Contact an authorized service center for service if none of the above. |
| PRE HI ENGINE TEMP lamp lights. Engine continues to operate. | Indicates engine has begun to overheat and engine temperature has risen to approximately 215°F (102°C) or coolant level is low on optionally wired sets. | A. Reduce load if possible by turning off non-critical loads. b. Check air inlets and outlets and remove any obstructions to airflow. If engine can be stopped, follow procedure in step 3. |
| PRE LO OIL PRES lamp lights. Engine continues to operate. | Indicates engine oil pressure has dropped to 20 psi (138 kPa). | If generator is powering critical loads and cannot be shut down, wait until next shutdown period and then follow step 5 procedure. If engine can be stopped, follow procedures in step 5. |
| SWITCH OFF lamp flashes | Indicates Run/Stop/Remote switch is in the Stop position which will prevent automatic starting if an automatic transfer switch is used. Move the Run/Stop/Remote switch to the Remote position for automatic starting. | |
| SWITCH OFF lamp flashes. | Move the Run/Stop/Remote switch to the Remote position for automatic starting. | |
| The FAULT 1 or FAULT 2 fault lamp lights. Engine shuts down immediately, engine runs for several seconds and then shuts down, or engine continues to run. | Engine standard undesignated fault functions are programmed to shut down the set when a fault is sensed. Fault 1 is time delayed while Fault 2 is immediate. The nature of the fault is an optional selection that is determined when the set installation is designed. The undesignated fault functions may also be programmed for non-shutdown or non-time delay. | |
| The O/U VOLTAGE lamp lights | Contact an authorized service center for service. | |
| The OVERLOAD lamp lights. Engine shuts down | The line circuit breaker is located in the output box or ATS. If load exceeds generator current rating, the breaker will trip preventing the generator from being overloaded and the genset will shut down. Locate the source of overload and correct as necessary. Manually reset breaker to reconnect the load to the generator. |
Fault codes and symptom→remedy steps extracted from this controller’s service/owner documentation; verify against the official manual before servicing. Aggregated from the service documentation of generator sets built on this controller.