The Cummins/Onan HGJAA is a generator set powered by a Cummins/Onan Series HGJAA & HGJAD engine. It is available at 240 V and 480 V, 3-phase and rated 65.7 A. Starting uses 2 batteries rated 430 CCA at 12 V.
High Pressure LPG Gensets: Drain the LPG system of accumulated sludge by opening the sludge drain valve.
—
5 hr
Oil
API performance Class SJ, SH or SG engine oil, which may be in combination with performance Class CH-4, CG-4 or CF-4 (for example: SJ/CH-4). Also look for the SAE viscosity grade.
2.0 quarts
—
Common questions
What engine does the Cummins/Onan HGJAA use?
The Cummins/Onan HGJAA is powered by the Cummins/Onan Series HGJAA & HGJAD engine.
Troubleshooting
31
Fault codes
Code
Meaning
2
Low Oil Pressure Fault
3
Service Check Fault
4
Overcrank
12
Overvoltage
13
Undervoltage
14
Overfrequency
15
Underfrequency
17
Fuel Pump Fault
19
Governor Actuator (EFI Only)
22
Governor Actuator Overload (EFI Only)
23
Oil Pressure Switch Fault
27
Voltage Sense Lost
29
High Battery Voltage
31
Overspeed Fault
32
Low Cranking Speed Sense
33
Fault Code 3 - Fault Code 33
35
Control Card Failure
36
Generator Set Stopped Without Fault Condition - Fault Code 36
37
Invalid Set Configuration
38
Field Overload (Overvoltage)
41
Alternator Rotor Fault
42
Processor Fault - Fault Code 42
43
Processor Fault - Fault Code 43
45
Speed Sense Fault
47
Ignition Fault
48
Field Sense Fault
51
Processor Failure - Fault Code 51
52
Fuel Injector Fault (EFI Only)
54
MAT Sensor Fault (EFI Only)
56
MAP Sensor Fault (EFI Only)
57
Overprime Fault
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Service, wear & replacement parts referenced for this model and its engine — confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.