With Electronic Controls

1. If the Air Mix Door Motor is displaced from its proper position, it will automatically calibrate itself to the proper position if the Battery power is removed from the Electronic A/C Control Assembly. To recalibrate the Air Mix Door Motor, disconnect then reconnect the Battery.
2. If a low Freon fault Code 9 is set, recharge the A/C System then reset the code by disconnecting and reconnecting the Battery.
3. Make sure that ground G200 is clean and tight.
4. Check Fuse 3. If open, check for a short to ground in CKT 640.
5. Check Fuse 6. If open, check for a short to ground in CKT 50.

With Engine warm and running in idle:
6. Check manifold vacuum at the black hose from the Engine to the Vacuum Tank.
7. Check for vacuum at the violet hose from the Vacuum Tank to the Solenoid Module.
8. Check that the vacuum hoses from the Solenoid Module to the Vacuum Actuators are connected and in good condition.

Check for a broken (or partially broken) wire inside of the insulation which could cause system failure bur prove "GOOD" in a continuity/voltage check.

Check for proper installation of aftermarket electronic equipment which may affect the integrity of other systems.