Test C: Heater-A/C Control Assembly Test

1. Remove connector from the Heater and A/C Control Assembly. Measure the voltage to ground at the following terminals.

Test C Heater And A/C Control Assembly Test:

^ If all voltages are correct but indicators don't light, replace the Heater and A/C Control Assembly. If indicators are good, proceed to step 2.
^ If voltage is not correct at terminal D, check Fuse 14 and ORN wire (40) for an open or short to ground.
^ If voltage is not correct at terminal J, check Fuse7 and the BRN wire (50) for an open or short to ground.
^ If voltage is not correct at Terminal 7, check the WHT/BLK wire (964) for an open. If wire is good, complete Test B. Test B: Blower Off Relay Test

2. Reconnect the Heater and A/C Control Assembly connector and select an operating mode. Turn Ignition Switch to OFF for several seconds, then turn it back to RUN. Check that Heater and A/C Control Assembly returns to same mode setting as before turned off. Make test using several different modes.

^ If the A/C System does not return to the same mode and all voltages are correct, replace the Heater and A/C Control Assembly.

3. Move the Blower Speed Control Switch through all positions.

^ Check that proper window is lighted in each position.
^ If all windows do not light, replace or repair the Blower Speed Control Switch.
^ If all voltages are correct but indicators don't light, replace the Heater and A/C Control Assembly.