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Home >> Ford >> 2008 >> F 150 2WD V8-5.4L >> Repair and Diagnosis >> Heating and Air Conditioning >> Testing and Inspection >> Pinpoint Tests >> Test G: The HVAC Module - EATC System Is Inoperative, Intermittent Or Incorrect Operation
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Test G: The HVAC Module - EATC System Is Inoperative, Intermittent Or Incorrect Operation

PINPOINT TEST G: THE HVAC MODULE - EATC SYSTEM IS INOPERATIVE, INTERMITTENT OR INCORRECT OPERATION

Normal Operation
Under normal operation, the HVAC module - electronic automatic temperature control (EATC) receives a ground through circuit 875 (BK/LB). The HVAC module - EATC is supplied constant battery voltage through circuit 729 (RD/WH) and ignition switched voltage through circuit 296 (WH/VT).

This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- HVAC module - EATC


G1-G6:






G7-G13:






G13-G14:




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