With HVAC System - Automatic - Manual Controls

1. Check the LOW BLOWER Fuse in the fuse block an open. If open, check circuit 40 for a short to ground.
2. Check the HIGH BLOWER Fuse in the fuse block for an open. If open, check circuit 141 for a short to ground.
3. Make sure G200 is clean and tight.
4. If the heater-A/C control is completely inoperative, check for poor connections at the heater-A/C control connector C1.
^ Check for a broken (or partially broken) wire inside of the insulation which could cause system malfunction but prove GOOD in a continuity/voltage check with a system disconnected. These circuits may be intermittent or resistive when loaded, and if possible, should be checked by monitoring for a voltage drop with the system operational (under load).
^ Check for proper installation of aftermarket electronic equipment which may affect the integrity of other systems. Refer to General Troubleshooting Procedures. Diagnostic Aids
^ Refer to System Diagnosis.