Automatic Transmission

Vehicle Speed Signal Circuit Troubleshooting

Special Tools Required
Test harness 07LAJ-PT3020A

A/T

Before testing, check the No. 9 (10 A) fuse in the under-hood fuse/relay box and the No. 10 (7.5 A) fuse in the under-dash fuse/relay box.

1. Start the engine, and check the malfunction indicator lamp (MIL).

Does the MIL come and stay on?

YES - Troubleshoot the PCM DTC, and recheck.

NO - Go to step 2.

2. Check the multiplex control unit DTC.

Is the DTC indicated?

YES - Troubleshoot the DTC, and recheck.

NO - Inspect the connector and socket terminals of the gauge assembly connectors. If the terminals look OK, substitute a known-good gauge assembly and retest. If the problem is fixed, replace the gauge assembly. If the problem is not fixed, replace the PCM.