Troubleshoot the interior lights. Start by checking the No. 14 (7.5 A) fuse in the under-dash fuse/relay box. If the fuse is OK, check for an open in the wire between the under-dash fuse/relay box and the audio unit.■
Turn the ignition switch to LOCK (0).
Disconnect the audio unit connector A (17P).
Disconnect the gauge control module (tach) 36P connector.
Check for continuity between the audio unit connector A (17P) terminal No. 1 and gauge control module (tach) 36P connector terminal No. 14.