P0204

DTC P0204
Fuel Injector fault - cylinder 4 Drive cycle A:Signal missing.

Possible causes by suggested order of priority:
- Injector 4 open circuit.
- Injector 4 short circuit.
- Injector 4 driver (in ECM) stuck on.
- Injector 4 driver (in ECM) stuck off.
- Fuse condition - F1 Engine Compartment Fusebox
- Open circuit - C525/2 (NO) to C571/1 (NO).
- Open circuit - C525/1 (YN) to C636/40 (YN).
- Connector(s) C525,ECM C636 (B).

Injector 4 open circuit.
- Check resistance > 1M Ohm

Injector 4 short circuit.
- Check resistance < 5.0 Ohm

Injector 4 driver (in ECM) stuck on.
- Injector 4 driver (in ECM) stuck on.
- Faulty ECM - Drive always energized (injecting) when ignition on.
- Harness cable connected to C525/1 (YN) shorted to ground - Valve always energized (injecting).
- Use multimeter to manually check components.

Injector 4 driver (in ECM) stuck off.
- Injector 4 driver (in ECM) stuck off.
- Faulty ECM - Injector never energized (no injection).
- Harness cable connected to C525/1 (YN) shorted to battery positive - Injector never energized (no injection).
- Use multimeter to manually check components.

Fuse condition - F1 Engine Compartment Fusebox
- Check for fuse not correctly inserted, fuse blown, fuse connections loose, damaged or corroded.
- Certain diagnostics may also perform further checks to try and narrow down the fault. Eg Check if other circuits fed by the same fuse are also experiencing problems

Open circuit - C525/2 (NO) to C571/1 (NO).
- Check resistance > 1M Ohm

Open circuit - C525/1 (YN) to C636/40 (YN).
- Check resistance > 1M Ohm

Connector(s) C525,ECM C636 (B).
- Check for connector not correctly latched, backed out pins, damaged pins, corroded pins