Vehicle Speed Signal Circuit Troubleshooting: A/T

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

   1. YES  - Troubleshoot the PCM DTC (see GENERAL TROUBLESHOOTING INFORMATION ), and recheck.
   2. NO  - Go to step 2.
2. Check the multiplex control unit DTC (see TROUBLESHOOTING ).

   Is the DTC indicated? 

   1. YES  - Troubleshoot the DTC (see TROUBLESHOOTING ), and recheck.
   2. 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.