The Computer Board (CCB) is a generator-set controller. It is used on generator sets from Generac, including the NP-30G.
| Code | Meaning | Remedy |
|---|---|---|
| C1 | Low Oil Pressure Shutdown | Check the engine oil level. |
| C2 | High Temperature Shutdown | |
| C4 | Low Voltage Shutdown | Disconnect all loads the generator might power by whatever means provided, such as the recreational vehicle’s main circuit breaker. |
| M01 | Low Oil Pressure Shutdown | Check the engine oil level. If necessary, add oil to the FULL mark. |
| M02 | High Temperature Shutdown | |
| M03 | Overspeed Shutdown | Do not attempt a manual adjustment to control engine speed. |
| M04 | Low Voltage Shutdown | |
| QA | W WARNING | |
| S1 | Overspeed Shutdown | Do not attempt a manual adjustment to control the engine speed. |
| T1 | High Temperature Shutdown | |
| V1 | Low Voltage Shutdown |
| Symptom | Cause | Remedy |
|---|---|---|
| AC output turns off intermittently. Then, engine runs at idle for 5 seconds. Finally, AC turns back on and unit runs normally | CCG board failure | Replace CCG circuit board |
| AC voltage is available to the Wire 66 and 77 terminals at the Battery Charge Rectifier, but no voltage or a low voltage is measured between the BCR's Wire 55 terminal and ground | The Battery Charge Rectifier (BCR) is defective | |
| AC voltage present at Wires 66 and 77 but DC voltage NOT present between Battery Charge Rectifier Wire 55 and frame ground | Battery Charge Rectifier (BCR) is defective | Replace Battery Charge Rectifier |
| AC voltage was present at the Wires 66 and 77 terminals of the Battery Charge Rectifier, but DC voltage is NOT present between the Battery Charge Rectifier's Wire 55 and frame ground | The Battery Charge Rectifier (BCR) is defective | |
| AC voltage was present at the Wires 66 and 77 terminals, but DC voltage is NOT present between the Battery Charge Rectifier's Wire 55 and frame ground | The Battery Charge Rectifier (BCR) is defective | |
| Battery charge winding resistance not within specification (Wires 66 to 55 = 0.037-0.042 Ohm; Wires 77 to 55 = 0.037-0.042 Ohm) | Stator Assembly defective | Replace Stator Assembly |
| Engine can be started, but shuts down after several seconds | A timing detection failure may have occurred (Timing winding, Wires TIM1, TIM2) | |
| Engine cranks but will not start | Low fuel level | Replenish fuel supply |
| Engine cranks but won't start | Out of fuel | Replenish fuel |
| Engine does not accelerate when load is applied. After 10 seconds, engine shuts down | Carburetor linkage sticking with throttle stuck closed | Repair sticking throttle |
| Engine shutdown initiated by CCG board | Over-voltage | |
| Engine shuts down but overspeed above 4500 rpm did not occur | One of four power windings in Stator is open | Repair/replace bad wire(s) AC1/AC2 or SL1/SL2 or replace Stator |
| Engine speed and AC output voltage erratic under constant load. AC output does not turn off intermittently | Stepper Motor failure | Replace Stepper Motor |
| Engine speed and output voltage are erratic under constant load, but the AC output does not turn off intermittently | Erratic timing detection may have occurred (Timing winding, Wires TIM1, TIM2) | |
| Engine speed is maintained and no-load voltage is good. However, when load is applied output voltage drops and engine shuts down | Carburetor linkage sticking with throttle partly open | Repair sticking throttle |
| Engine starts but Stepper Motor does not move. Shut down occurs after several seconds | Power Supply winding (PS1, PS2) is open | Repair or replace bad wire(s) PS1/PS2 or replace Stator |
| Engine starts hard, runs rough, low full load power | Air cleaner plugged or damaged | Clean or replace as needed |
| Engine starts, accelerates, shuts down at 4500 rpm | Carburetor linkage sticking with throttle stuck open | Repair sticking throttle |
| Engine starts, but Stepper Motor does not move, and engine shuts down after several seconds | CCG circuit board's micro-controller may not be operating | |
| Engine starts, but Stepper Motor does not move. Engine appears to operate too slowly; Engine is not able to handle the load and unit operates at low AC output voltage; After several seconds under load, AC output voltage is turned off (overload condition) | A failure of the circuit board's Stepper Motor drive | |
| Engine starts, but Stepper Motor does not move. Engine appears to operate too slowly; engine is not able to handle the load and unit operates at low AC output voltage; after several seconds under load, AC output voltage is turned off (overload condition) | Failure of the circuit board's Stepper Motor drive | |
| Engine starts, but Stepper Motor does not move. The engine accelerates uncontrollably and shuts down when engine speed exceeds 4500 rpm | A failure of the circuit board's Stepper Motor drive | |
| Engine starts, but the Stepper Motor does not move, and engine shuts down after several seconds | The CCG circuit board's micro-controller may not be operating | |
| Engine starts, but then shuts down after startup | A problem could exist in either the generator computer system or in the engine DC control system | Isolate the CCG system using the test fixture; if the engine starts and shuts down, check engine oil level (if oil level is low, replenish as necessary; if oil level is NOT low, go to Test 26); if engine was shutting down after startup, but does not shut down during this test, the problem is in the CCG system, go to Test 27 |
| Engine starts, shuts down when Start/Stop switch is released | Engine oil is low | Check oil; add as needed |
| Engine will not crank | 15 amp fuse bad | Replace bad fuse |
| Engine will not start (spark plug DRY) | Carburetor gasket(s) leaking | Adjust or repair carburetor or fuel system as necessary |
| Engine will not start (spark plug WET) | Overchoking | Adjust or repair carburetor or fuel system as necessary |
| Engine will not start or starts hard and runs rough | A failure in the engine's mechanical system | Perform a compression check; if compression is poor, look for one or more of the following possible causes: Loose cylinder head bolts; Failed cylinder head gasket; Burned valves or valve seals; Insufficient valve clearance; Warped cylinder head; Warped valve stem; Worn or broken piston ring(s); Worn or damaged cylinder bore; Broken connecting rod |
| Engine will not start or starts hard and runs rough (poor compression) | Loose cylinder head bolts | |
| Engine will not start, spark plug is DRY | Carburetor gasket(s) leaking; Fuel line plugged or shutoff valve not opening; Intake valve stuck closed; Inoperative fuel pump; Clogged fuel filter | Adjust or repair carburetor or fuel system as necessary |
| Engine will not start, spark plug is WET | Overchoking; Water in fuel; Excessively rich fuel mixture; Intake valve stuck open | Adjust or repair carburetor or fuel system as necessary |
| Engine won't crank | 15 amp fuse is blown | Replace 15 amp fuse |
| Engine won't start or starts hard and runs rough | Carburetion | Make sure the fuel tank has an ample supply of clean fresh gasoline (gasoline fuel systems) or gaseous fuel; make sure all shutoff valves are open; adjust the carburetor as outlined on Page 3.4-2; make sure the automatic choke is working properly and that the choke closes completely; adjust or repair carburetor or fuel system as necessary |
| Genistor fails resistance/continuity tests | Genistor defective | Replace Genistor |
| No AC voltage can be measured across Stator connections at the Battery Charge Rectifier (BCR) | An open circuit condition probably exists in Wire 66 (Brown), or Wire 77 (Brown) | |
| No AC voltage is measured at the Wires 66 and 77 terminals of the Battery Charge Rectifier, with the unit running | An open circuit exists in the wire 66 or 77 circuit | |
| No AC voltage measured at Wires 66 and 77 terminals of the Battery Charge Rectifier with unit running | Open circuit exists in the wire 66 or 77 circuit | |
| Overvoltage condition and speed control system cannot reduce output voltage | Carburetor linkage sticking with throttle stuck partly open | Repair sticking throttle |
| Premature high temperature shutdowns | Some early production units were equipped with a 265° F. switch | The 265° F. switch should be removed and replaced with the Part No. 94090 switch |
| Priming function does not work | 15 amp fuse is bad | Replace bad fuse |
| Problem in AC generator system when other components tested good | CCG circuit board | Replace the CCG circuit board and check unit operation |
| Start/Stop switch at Stop, engine continues to run | Defective Start/Stop switch | Replace switch |
| The engine can be started, but shuts down after several seconds | A timing detection failure may have occured (Timing winding, Wires TIM1, TIM2) | |
| The engine speed and output voltage are erratic under constant load, but the AC output does not turn off intermittently | Erratic timing detection may have occured (Timing winding, Wires TIM1, TIM2) | |
| The engine starts, but the Stepper Motor does not move, and engine shuts down after several seconds | The CCG circuit board's micro-controller may not be operating | |
| Under heavy load, output turns off and engine speed drops to idle | CCG circuit board failure | Replace CCG circuit board |
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.