C1256

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(Part 2 Of 2):

CIRCUIT DESCRIPTION
This DTC identifies a motor that cannot be energized due to an open in its circuitry. This malfunction will not allow proper front ABS operation.

CONDITIONS FOR SETTING THE DTC
DTC C1256 can be set only when the motor is commanded OFF. If the EBCM detects an out of range voltage in either of the left front motor circuits indicating an open circuit, a malfunction exists.

ACTION TAKEN WHEN THE DTC SETS
An open motor will not activate when requested. 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
Using the scan tool, select manual control function, and exercise motor movement of affected channel in both directions while applying light pressure on the brake pedal.

If erratic or jumpy brake pedal movement is detected while performing an apply or release function of the motor, an intermittent malfunction may be indicated.


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

If the malfunction is not current, wiggle the wires of the affected channel and check if the DTC rests. this will help to pinpoint an intermittent malfunction in the motor circuitry or connections.

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.