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Home >> Ford >> 2008 >> E 150 V8-5.4L >> Repair and Diagnosis >> Heating and Air Conditioning >> Testing and Inspection >> Pinpoint Tests >> Test H: The Blower Motor Does Not Operate Correctly
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Test H: The Blower Motor Does Not Operate Correctly

PINPOINT TEST H: THE BLOWER MOTOR DOES NOT OPERATE CORRECTLY

Normal Operation
Under normal operation, the blower motor is provided a ground from the blower resistor through circuit 261 (OG/BK). The resistor gets a ground from circuit 57 (BK) in the lowest blower setting. In MED-LO and MED-HI the resistor gets a ground through circuit 260 (RD/OG) or 269 (LB/OG), depending on selected speed. In HI, the blower motor is grounded directly through the blower switch from circuit 261 (OG/BK) to circuit 57 (BK). The blower switch receives its ground from circuit 57 (BK).

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Blower motor resistor
- Blower motor switch

H1-H3:






H3-H4:






H5-H7:






H8-H10:




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