C1287

Part 1 Of 4:

Part 2 Of 4:

Part 3 Of 4:

Part 4 Of 4:

CIRCUIT DESCRIPTION
DTC C1287 identifies one of the following conditions:
^ An open or short to voltage between the EBCM/EBTCM and the red BRAKE warning indicator.
^ An open driver that does not allow the EBCM/EBTCM to illuminate the red BRAKE warning indicator.

DTC C1287 will only occur if an ABS malfunction is detected that may degrade base brake operation.

A short to ground in the circuit cannot be detected because the EBCM/EBTCM is not the only device controlling the red BRAKE warning indicator. The following components may also turn on the red BRAKE warning indicator:
^ The parking brake indicator switch
^ The brake fluid level indicator sensor

CONDITIONS FOR SETTING THE DTC
DTC C1287 can set during the three second bulb check and after completing initialization.

A malfunction exists if the red BRAKE warning indicator circuit voltage is out of specification. If the circuit voltage is out of specification, an open circuit or a short to voltage exists.

ACTION TAKEN WHEN THE DTC SETS
^ A malfunction Diagnostic Trouble Code (DTC) stores.
^ The ABS/ETS/TCS does not disable.
^ The amber ABS/ETS/TCS warning indicator will flash to indicate a serious problem if the following conditions occur:
1. The EBCM/EBTCM commands the red BRAKE warning indicator on due to an ABS malfunction that may degrade base brake operation.
2. The red BRAKE warning indicator cannot turn on.

CONDITIONS FOR CLEARING THE DTC
^ The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used.
^ 100 drive cycles pass with no DTC(s) detected.

DIAGNOSTIC AIDS
The following conditions may cause an intermittent malfunction:
^ A poor connection
^ Rubbed-through wire insulation
^ A broken wire inside the insulation

Use the enhanced diagnostic function of the Scan Tool in order to measure the frequency of the malfunction.

Refer to the Scan Tool manual for the procedure. If the Scan Tool is not available, lift the parking brake handle in order to verify proper indicator operation and continuity of CKT 3 and CKT 39.

Thoroughly inspect any circuitry that may cause the intermittent complaint for the following conditions:
^ Backed out terminals
^ Improper mating
^ Broken locks
^ Improperly formed or damaged terminals
^ Poor terminal-to-wiring connections
^ Physical damage to the wiring harness

IMPORTANT: Zero the J 39200 test leads before making any resistance measurements. Refer to the J 39200 user's manual.