The JDEC electronic is a generator-set controller. It is used on generator sets from Atlas Copco, including the QAS generator set with JDEC system.
| Code | Meaning |
|---|---|
| 18 | Engine coolant temperature input voltage high |
| 19 | Engine coolant temperature input voltage low |
| 21 | Sensor supply voltage high |
| 22 | Sensor supply voltage low |
| 23 | Engine oil pressure input voltage high |
| 24 | Engine oil pressure input voltage low |
| Blink 26 | Manifold air temperature input voltage low |
| Blink 28 | ECU error |
| Blink 32 | When reading blink codes, signifies start of active fault codes |
| Blink 33 | When reading blink codes, signifies start of stored fault codes |
| Blink 37 | Fuel temperature input voltage high |
| Blink 38 | Fuel temperature input voltage low |
| Blink 39 | Crank position input error |
| Blink 42 | Engine over speed moderate or extreme |
| Blink 54 | ECU power down error |
| Blink 62 | Engine coolant temperature high - least severe |
| Blink 63 | Engine coolant temperature high - moderately severe |
| Blink 64 | Engine oil pressure moderately low |
| Blink 65 | Engine oil pressure extremely low |
| Blink 66 | Manifold air temperature moderately high |
| Blink 68 | Fuel de-rate |
| Blink 69 | Engine coolant temperature high – most severe |
| Blink 71 | Pump control valve closure too long |
| Blink 72 | Pump control valve closure too short |
| Blink 73 | Pump solenoid circuit open |
| Blink 74 | Pump solenoid circuit severely shorted |
| Blink 75 | Pump control valve closure not detected |
| Blink 76 | Pump solenoid circuit moderately shorted |
| Blink 77 | Pump solenoid current high |
| Blink 78 | Security violation |
| Blink 79 | Internal ECU error |
| Blink 81 | Fuel temperature moderately high |
| Blink 82 | Engine protection shutdown |
| Blink 83 | Auxiliary engine shutdown switch active |
| Blink 88 | When reading blink codes, signifies no fault codes in buffer |
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.