Code 94 - Brake Switch Contacts Always Closed: Notes

This test determines proper operation of brake switch. ABS is activated when brake switch is on and turned off when brake switch is off. If brake switch is always on, ABS operation will always be requested, resulting in potential modulator cycling on rough roads. This failure will result in a dead battery, due to brakelights staying on.

Code 94 can set when vehicle speed reaches 25 MPH and brake switch is never off during 2 consecutive drive cycles. Code will be stored, but ABS will not be disabled.

NOTE: Test numbers refer to numbers on diagnostic chart. Use only 10-megohm (minimum) DVOM for all voltage and resistance tests. For identification of circuits and terminals referenced in charts and text, see WIRING DIAGRAMS .

Fig 1: Code 94 Diagnostic Flow Chart

Checks if malfunction is currently present or brakes light are on.
Isolates malfunction to either a malfunctioning or misadjusted brake switch, or a short to voltage in brake switch input circuit.
Checks for unwanted voltage on brake switch input circuit.
Ensures malfunction is not due to poor terminal contact or EBCM/EBTCM.