Measure voltage between ECM/PCM connector terminal A26 and body ground. ECM/PCM CONNECTOR A (31P) Wire side of female terminals Is there about 5 V? YES - Repair open in the wire between the ECM/PCM (A26) and TDC sensor. NO - Go to step 11. Turn the ignition switch OFF. Disconnect ECM/PCM connector A (31P). Check for continuity between ECM/PCM connector terminal A26 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 (A26) and the TDC sensor. NO - Substitute a known-good ECM/PCM and recheck (see page 11-313). If symptom/indication goes away, replace the original ECM/PCM.

DTC P1607: Malfunction in ECM/PCM Internal Circuit Reset the ECM/PCM (see page 11-312). Turn the ignition switch ON (II). Wait 40 seconds. Is DTC P1607 indicated? YES - Substitute a known-good ECM/PCM and recheck (see page 11-313). If symptom/indication goes away, replace the original ECM/PCM. NO - Intermittent failure, system is OK at this time.