Antilock Braking System (ABS)

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Part 2 Of 2:

CIRCUIT DESCRIPTION
The brake lamp switch circuit is an input to the EBTCM. It is used to monitor the status of the brake lamp switch. This is important because ABS is activated and TCS is inhibited when the brake switch is on and ABS is inhibited when the brake switch is off.

CONDITIONS FOR SETTING THE DTC
- There is an open in the brake lamp switch circuit.
- Both the left. and the right brake lamp bulbs are open.
- There is a misadjusted or a malfunctioning brake lamp switch.
- There is a malfunction in the EBTCM.

ACTION TAKEN WHEN THE DTC SETS
- A malfunction DTC is stored.
- The ABS and the TC indicator lamps are turned on.
- The ABS and the TCS are disabled.

CONDITIONS FOR CLEARING THE DTC
- The condition for the DTC is no longer present.
- The scan tool Clear DTCs function is used.
- 100 drive cycles have passed with no DTCs detected.

DIAGNOSTIC AIDS
- Perform a thorough inspection of the wiring. Perform a thorough inspection of the connectors.
- Failure to carefully and fully inspect the wiring and the connectors may result in misdiagnosis. Misdiagnosis causes part replacement with reappearance of the malfunction.

TEST DESCRIPTION
The number(s) below refer to the step number(s) on the diagnostic table.
2. If the brake lamps operate properly, the integrity of the circuit up to splice S206 is verified.
3. This step verifies if the brake switch input is being received by the EBTCM.
4. If both brake lamp bulbs are not open, the malfunction is between splice S206 and the clamp cruise fuse 15, or is an open fuse.