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Home >> Ford >> 2008 >> E 250 V8-4.6L >> Repair and Diagnosis >> Heating and Air Conditioning >> Testing and Inspection >> Pinpoint Tests >> Test F: Temperature Control Is Inoperative/Does Not Operate Correctly
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Test F: Temperature Control Is Inoperative/Does Not Operate Correctly

PINPOINT TEST F: TEMPERATURE CONTROL IS INOPERATIVE/DOES NOT OPERATE CORRECTLY

Normal Operation
Under normal operation, the temperature blend door actuator is supplied voltage on circuit 489 (PK/BK) and ground on circuit 57 (BK). As the temperature selection changes it varies the voltage on circuit 437 (YE/LG) to the temperature blend door actuator. The temperature control potentiometer receives reference voltage from the temperature blend door actuator through circuit 436 (RD/LG). Ground for the temperature control potentiometer is supplied from the temperature blend door actuator through circuit 438 (RD/WH).

This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- Temperature blend door actuator
- Temperature control potentiometer
- Stuck or bound linkage or door

F1-F2:






F3-F4:






F5-F7:






F7-F9:






F10-F11:




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