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Test Q: The Steering Wheel Control Switch Is Inoperative/Does Not Operate Correctly

PINPOINT TEST Q: THE STEERING WHEEL CONTROL SWITCH IS INOPERATIVE/DOES NOT OPERATE CORRECTLY


Q1:






Q1-Q3:






Q3-Q5:






Normal Operation
Under normal operation, the electronic automatic temperature control (EATC) module senses the resistance (depending on what button is pressed) from the steering wheel control switch through circuit 1070 (BN/LB). Ground for the steering wheel control switch is provided through circuit 57 (BK).

Possible Causes
- An open in circuit 57 (BK) or 1070 (BN/LB)
- A short to ground circuit 1070 (BN/LB)
- Steering wheel control switch
- Electronic automatic temperature control (EATC) module