DTC 54

Fig. 026 - Chart - Code Constant High Voltage From M/C Solenoid To ECM.:

Code 54 Indicates Constant High Voltage at ECM Terminal 18

A shorted mixture control solenoid or a wiring short to 12V would cause the solenoid to remain in the full rich position, causing excessive fuel consumption, and excessive exhaust odor.

1. Check the M/C solenoid resistance to determine if the fault is in the solenoid or ECM harness/ECM. A normal solenoid has about 18-32 ohms of resistence.
- After replacing a faulty M/C solenoid, a system performance test is necessary to be certain the M/C solenoid was the only faulty part. It may have caused the ECM to fail, so a code may be reset.

2. Verifies reason for high voltage to Terminal "18" is a faulty ECM or a short to 12V on that wire.
- If the test light to ground lights at the M/C solenoid test lead with both ends of the harness disconnected, then there is a short to 12V in the wire.