With HVAC System - Automatic - Electronic Controls

1. Check the RADIO, HVAC Fuse in the fuse block for an open. If open, check for a short to ground in circuit 640.
2. Check the HVAC Fuse in the fuse block for an open. if open, check for a short to ground in circuit 41.
3. Check the HIGH BLOWER Fuse in the fuse block for an open. If open. check for a short to ground in circuit 40.
4. Make sure G200 is clean and tight.
5. Check for corrosion on connector terminals at the blower motor and the blower motor control module.
6. If the blower motor can be controlled in either the manual mode or the AUTO mode but not in both, replace the heater-A/C control.
7. Check for any set trouble codes before performing any diagnosis. If any HVAC trouble codes are present, refer to HVAC Air Delivery and Temperature Controls (CJ2) for diagnostic procedures. Testing and Inspection
^ 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.