( TF09E8KG24100032581FAAT00 )
HVAC Control Power and Ground Circuit Troubleshooting
  1. Check the No. 10 (7.5 A) fuse in the under-dash fuse/relay box.
Is the fuse OK?
YES -
Go to Step 2 .
NO -
Replace the fuse, and recheck. If the fuse blows again, check for a short in the No. 10 (7.5 A) fuse circuit.■
  1. Disconnect the HVAC control unit 12P connector.
  1. Turn the ignition switch to ON (II).
  1. Measure the voltage between the HVAC control unit 12P connector No. 7 terminal and body ground.
Is there battery voltage?
YES -
Go to Step 5 .
NO -
Repair open in the wire between the No. 10 (7.5 A) fuse in the under-dash fuse/relay box and the HVAC control unit.■
  1. Turn the ignition switch to LOCK (0).
  1. Check for continuity between the HVAC control unit 12P connector No. 9 terminal and body ground.
Is there continuity?
YES -
Check for loose wires or poor connections at the HVAC control unit 12P connector. If the connections are good, substitute a known-good HVAC control unit, and recheck.■
NO -
Check for open in the wire between the HVAC control unit and body ground. If the wire is OK, check for poor ground at G502. ■