C1218

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CIRCUIT DESCRIPTION
Ignition voltage is supplied to terminal 86 of the Electronic Brake Control Relay. The EBCM is then able to energize the pull-in coil by completing the ground circuit at terminal 2 of the EBCM. The magnetic field created closes the Electronic Brake Control Relay contacts and allows battery voltage and current to be supplied to the EBCM, which supplies power to the motors and solenoids.

CONDITIONS FOR SETTING THE DTC
DTC C1218 can be set after the EBCM commands the Electronic Brake Control Relay ON. This test monitors the availability of current/voltage to the motors and solenoids. A malfunction of this type will not allow voltage to be available to the motors and solenoids, therefore, ABS operation would not be allowed if required. DTC C1286 is set with DTC C1218 if the rear channel is not expected to be in the home position.

ACTION TAKEN WHEN THE DTC SETS
A malfunction DTC is stored, ABS is disabled, and the ABS indicator lamp is turned ON.

CONDITIONS FOR CLEARING THE DTC
Conditions for the malfunction are no longer present and the scan tool CLEAR DTCs function is used. One hundred ignition switch key cycles have passed with no malfunctions detected.

DIAGNOSTIC AIDS
An intermittent malfunction is most likely caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation.

The frequency of the malfunction can be checked by using the ENHANCED DIAGNOSTIC function of the scan tool.

Any circuitry that is suspected of causing the intermittent complaint should be thoroughly checked for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wiring connections or physical damage to the wiring harness.