DTC 34 - Injection Timing Stepper (Its) Motor Circuit Fault: Notes

The PCM controls injection timing with the injection timing stepper motor. To increase injection timing the PCM extends the stepper motor. To retard timing the PCM retracts the stepper motor. DTC 34 will set when:

• Engine operating at steady RPM.
• A 5 degree difference exists between measured and desired injection timing for 20.8 seconds.

1. This step determines if DTC 34 is the result of a hard failure or an intermittent condition.
2. This step checks for an open or short in the ITS coil 1 low circuit and the ITS coil 1 high circuit.
3. This step checks for an open or short in the ITS coil 2 low circuit and the ITS coil 2 high circuit.