Code 38, Brake Switch Circuit - 3.3L & 3.8L: Notes

Fig 1: Code 38, Brake Switch Circuit Diagram (3.3L A Body W/3T40)

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Fig 2: Code 38, Brake Switch Circuit Diagram (3.3L A Body W/4T60)

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Fig 3: Code 38, Brake Switch Circuit Diagram (3.3L N Body)

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Fig 4: Code 38, Brake Switch Circuit Diagram (3.8L C & E Bodies)

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Fig 5: Code 38, Brake Switch Circuit Diagram (3.8L H Body)

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Fig 6: Code 38, Brake Switch Circuit Diagram (3.8L W Body)

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Code 38 will set if no Code 24 is present, status at brake input terminal of control module has not changed from high to low and vehicle speed has been greater than 35 MPH and back to zero MPH a precalibrated number of times.

1. Jumpering the brake switch determines if the ECM and wiring for the brake switch are okay.
2. Determines if brake switch is out of adjustment or is faulty.
3. Verifies the voltage to the brake switch.