AVR (PowerCommand 320)
Part: Cummins A-503459
Price after code 214, 215, 221, or 224 diagnostics point to voltage regulation or field excitation.
$265
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Cummins Generator Error Codes
Cummins residential and industrial generators (PowerCommand, Onan, NGen, and QSX series) report faults through the PowerCommand controller display or the newer Onan digital controller. Codes are grouped by fault category.
For a brand-neutral lookup path, start with the generator fault-code hub and then choose the Cummins, Onan, Generac, Kohler, Honda, Champion, Westinghouse, Briggs, or DuroMax guide that matches the controller.
Cummins PowerCommand Error Codes (100-Series — Engine)
| Code | Fault Description | Common Cause | Action |
|---|---|---|---|
| 111 | Low oil pressure | Oil below 10 PSI | Check oil level, pressure sensor, wiring harness |
| 112 | High coolant temperature | Coolant above 210°F | Check coolant level, radiator, fan belt tension |
| 115 | Overcrank | Engine failed to start in programmed attempts | Check fuel supply, glow plugs, battery voltage |
| 118 | Low coolant level | Coolant below sensor level | Add coolant, pressure test for leaks |
| 122 | High exhaust temp | Exhaust restriction | Check muffler, exhaust piping, aftertreatment |
| 131 | Auxiliary shutdown | External shutdown signal | Check remote wiring, E-stop button |
| 134 | Common fault relay | Ground fault in remote wiring | Check all remote annunciator wiring |
| 141 | Overspeed | RPM above 115% rated | Check governor actuator, linkage, fuel regulator |
| 143 | Underspeed | RPM below 85% rated | Check fuel pressure, air filter, load capacity |
| 144 | WTS active | Wait to start cycle active | Normal on cold starts with glow plugs |
| 145 | Overspeed shutdown | RPM exceeded max safe | Check actuator, load shed, fuel pressure |
| 151 | Sensor supply fault | 5V reference shorted | Check all 5V sensor wiring, individual sensors |
| 152 | Crank timeout | Starter engaged too long | Check starter relay, wiring, battery voltage |
| 153 | High oil temp | Oil temperature above 250°F | Check oil cooler, engine load, oil condition |
200-Series — Generator/Electrical
| Code | Fault Description | Common Cause | Action |
|---|---|---|---|
| 214 | Generator overvoltage | Output > 110% rated | Test AVR, voltage adjust potentiometer |
| 215 | Generator undervoltage | Output < 90% rated | Test AVR, check for large motor starting loads |
| 221 | Loss of voltage sensing | AVR lost VT signal | Check voltage sensing wiring, fuses |
| 224 | Field overexcitation | Rotor field current too high | Test AVR control circuit, replace AVR |
| 225 | Field underexcitation | Rotor field current too low | Test rotating diodes, exciter stator |
| 231 | Battery charger fault | Charger not functioning | Test charger output, AC input to charger |
| 241 | Low battery voltage | Battery below 11.5V | Replace battery, check charger output |
| 242 | High battery voltage | Battery above 15.5V | Test charger regulator, battery condition |
| 251 | kW overload | Load exceeds 100% rating | Reduce load, check for short cycle loads |
| 252 | kW load shed | Load shed contact opened | Check ATS, load management controller |
300-Series — Controller/Communication
| Code | Fault Description | Common Cause | Action |
|---|---|---|---|
| 311 | Controller failure | PCM/PCC internal fault | Cycle power, replace controller if persists |
| 312 | Configuration fault | Parameters lost | Reload configuration, replace backup battery |
| 321 | Analog sensor fault | Sensor reading out of range | Check individual sensor wiring and values |
| 322 | Digital sensor fault | Switch input invalid | Test switch continuity, wiring for opens |
| 341 | Communication lost | CAN bus failure | Check terminating resistors, harness damage |
| 342 | J1939 data link fault | Engine ECM not communicating | Check J1939 wiring, ECM power supply |
| 351 | Event log full | Internal log memory full | Download and clear event log |
Most Common Cummins Generator Faults
Code 111 — Low Oil Pressure
The PowerCommand controller monitors oil pressure through a resistive sender or switch. Code 111 triggers when pressure drops below 10 PSI. Quick test: with a manual gauge installed at the engine block, compare reading to the controller display. A discrepancy means the sender is failing. Cummins senders typically read 10–150 ohms depending on pressure. An open circuit reads as zero pressure.
Code 145 — Overspeed Shutdown
The engine exceeded maximum RPM (typically 115% of rated). On Cummins quick-start generators, overspeed is often caused by a failed governor actuator that can’t close the throttle fast enough when load drops. Test: disconnect the actuator linkage and manually move the throttle — it should move freely without binding. A sticky throttle plate combined with a slow actuator causes overspeed when load sheds.
Code 214 — Generator Overvoltage
Output voltage exceeds 110% of nominal. This is usually a failed AVR (voltage regulator) or a loose voltage adjustment potentiometer. Test: with the generator running at no load, measure output voltage at the breaker. If voltage is above 130V on a 120V system, the AVR needs replacement. Cummins PowerCommand AVRs (part number A-503459) cost $180-$350.
Parts Reference
| Part | Approx Cost | Notes |
|---|---|---|
| AVR (PowerCommand 320) | $180-$350 | Cummins A-503459 |
| Oil pressure sender | $35-$65 | Cummins 4065897 |
| Governor actuator | $200-$500 | Cummins 4065931 |
| Coolant temp sensor | $25-$45 | Cummins 3045048 |
| Battery charger | $80-$150 | Cummins A-510141 |
Need Replacement Parts?
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