Operation CHARM: Car repair manuals for everyone.

Rear Wiper LED Flashing Once, Int. LED Flashing Three Times

THE MAIN TEMPERATURE ACTUATOR ON A ZONE SYSTEM DID NOT REACH COLD STOP.
1. Check if the correct HVAC control module was used.
2. Using a voltmeter, check the temperature door actuator wiring connector. Check Pin 1 for battery voltage. Move the HVAC control from the cold to hot position, and check Pin 5 voltage it should change from 0.5 - 4 volts to 3.5 - 4.5 volts. If voltage is OK, go to Step 3. If not OK, check for loose or corroded connector, open or shorted circuit and repair as necessary
3. Remove actuator, and check if gear pins are in the correct cam track or binding. If OK, go to Step 4 If not OK, repair as necessary.
4. Check for binding door, if door is binding repair as necessary If gears and door are OK, replace actuator.
5. Once repairs are completed repeat the Calibration Diagnostic and Cool-down test. Repeating the test is necessary to clear the fault codes.