Generac RD048 troubleshooting: 20 fault codes and 24 symptom-cause-remedy entries from the manufacturer's own service documentation.
Generac RD048 — full specs, parts & maintenance.
| Code | Meaning | Remedy |
|---|---|---|
| F1 | Open F1 5 amp fuse | Replace F1 5 amp fuse if fuse blows again.* |
| NOT ACTIVATED | Unit will not start in AUTO with utility loss | Refer to activation section in Owner's Manual. |
| HIGH TEMPERATURE | Unit shuts down during operation | Check ventilation around the intake, exhaust and rear of generator. Contact serving dealer if no obstruction is found. |
| OVERLOAD | Unit shuts down during operation | Clear alarm and remove household loads from the generator. Put back in AUTO and restart. |
| RPM SENSE LOSS | Unit was running and shuts down, attempts to restart | Clear alarm and remove household loads from the generator. Put back in AUTO and restart. If problem returns, contact servicing dealer to investigate possible fuel issue. |
| LOW OIL PRESSURE | Unit will not start in AUTO with utility loss | Check oil level. Add oil per Owner's Manual. Contact servicing dealer if oil level is correct. |
| RPM SENSE LOSS | Unit will not start in AUTO with utility loss | Clear alarm. From the MAIN menu on the control panel, navigate to the BATTERY MENU. Contact servicing dealer if battery is GOOD. Replace battery If CHECK BATTERY is displayed. |
| OVERCRANK | Unit will not start in AUTO with utility loss | Clear alarm. Attempt to start the unit in MANUAL. If it does not start or starts and runs rough, contact servicing dealer. |
| FUSE PROBLEM | Unit will not start in AUTO with utility loss | Check ATO 7.5 amp fuse. Replace with same type fuse if bad. Contact servicing dealer if fuse is good. |
| OVERSPEED | Unit will not start in AUTO with utility loss | Contact servicing dealer. |
| UNDER VOLTAGE | Unit will not start in AUTO with utility loss | Contact servicing dealer. |
| UNDERSPEED | Unit will not start in AUTO with utility loss | Contact servicing dealer. |
| MISWIRE | Unit will not start in AUTO with utility loss | Contact servicing dealer. |
| OVERVOLTAGE | Unit will not start in AUTO with utility loss | Contact servicing dealer. |
| LOW BATTERY | Warning active | Clear alarm. From the MAIN menu on the control panel, navigate to the BATTERY MENU. Contact servicing dealer if battery is GOOD. Replace battery If CHECK BATTERY is displayed. |
| BATTERY PROBLEM | Warning active | Contact servicing dealer. |
| CHARGER WARNING | Warning active | Contact servicing dealer |
| SERVICE SCHEDULE A | Warning active | Perform SERVICE SCHEDULE A maintenance; press ENTER to clear. |
| SERVICE SCHEDULE B | Warning active | Perform SERVICE SCHEDULE B maintenance; press ENTER to clear. |
| SERVICE SCHEDULE C | Warning active | Perform SERVICE SCHEDULE C maintenance; press ENTER to clear. |
| Symptom | Cause | Remedy |
|---|---|---|
| The engine will not crank | Fuse blown | Replace 7.5 amp fuse in generator control panel. Correct short circuit condition if fuse blows again. |
| The engine will not crank | Loose, corroded or defective battery cables | Tighten, clean or replace as necessary.* |
| The engine will not crank | Defective starter contact | Tighten, clean or replace as necessary.* |
| The engine will not crank | Defective starter motor | Tighten, clean or replace as necessary.* |
| The engine will not crank | Dead Battery | Charge or replace battery. |
| The engine cranks but will not start | Out of fuel | Replenish fuel. Turn on fuel valve. |
| The engine cranks but will not start | Defective fuel solenoid | * |
| The engine cranks but will not start | Defective fuel system | * |
| The engine cranks but will not start | No fuel to pump | Prime fuel system.* |
| The engine starts hard and runs rough | Air cleaner plugged or damaged | Check/replace air cleaner. |
| The generator is set to OFF, but the engine continues to run | Defective keypad | * |
| The generator is set to OFF, but the engine continues to run | Defective control board | * |
| There is no AC output from the generator | Main line circuit breaker is in the OFF (OPEN) position | Reset circuit breaker to ON (CLOSED) position. |
| There is no AC output from the generator | Generator internal failure | * |
| There is no transfer to standby after utility source failure | Defective transfer switch coil | * |
| There is no transfer to standby after utility source failure | Defective transfer relay | * |
| There is no transfer to standby after utility source failure | Transfer relay circuit open | * |
| There is no transfer to standby after utility source failure | Defective control logic board | * |
| Unit consumes large amounts of oil | Engine over filled with oil | Adjust oil to correct level. |
| Unit consumes large amounts of oil | Engine breather defective | * |
| Unit consumes large amounts of oil | Incorrect oil type or viscosity | See Engine Oil Recommendations. |
| Unit consumes large amounts of oil | Damaged gasket, seal or hose | Check for oil leaks. |
| Unit running in AUTO but no power in house | Check MLCB. Contact servicing dealer if MLCB is in the ON position. | |
| Unit will not start in AUTO with utility loss | Check screen for start delay countdown. If the start up delay is greater than expected, contact servicing dealer to adjust from 2 to 1500 seconds. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Documented causes: Fuse blown; Loose, corroded or defective battery cables; Defective starter contact; Defective starter motor. See the table for the matching fixes.
Documented causes: Out of fuel; Defective fuel solenoid; Defective fuel system; No fuel to pump. See the table for the matching fixes.
Documented causes: Defective transfer switch coil; Defective transfer relay; Transfer relay circuit open; Defective control logic board. See the table for the matching fixes.