PGM-FI System

MIL Circuit Troubleshooting (cont'd)

 11-86  

  1. Check for continuity between ECM/PCM connector terminal A20 and body ground.

ECM/PCM CONNECTOR A (31P)

Wire side of female terminals

Is there continuity?

YES - Repair short in the wire between the ECM/PCM (A20) and the EGR valve position sensor, knock sensor or TP sensor, or repair short in the wire between ECM/PCM (A8) and the knock sensor.

NO - Substitute a known-good ECM/PCM and recheck. If symptom/indication goes away, replace the original ECM/PCM.

  1. Measure voltage between body ground and ECM/PCM connector terminals E5.

ECM/PCM CONNECTOR E (31P)

Wire side of female terminals

Is there about 5 V?

YES - Substitute a known-good ECM/PCM and recheck. If the symptom/indication goes away, replace the original ECM/PCM.

NO - Go to step 63.

  1. Turn the ignition switch OFF.
  2. Disconnect the idle mixture adjuster (IMA) sensor 3P connector.
  3. Turn the ignition switch ON (II).