ABS - With Traction Control

DTC C1264 Part 1 Of 2:

DTC C1264 Part 2 Of 2:

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

CONDITIONS FOR SETTING THE DTC
DTC C1264 can be set only when the ABS motor is commanded off. If the EBCM/EBTCM detects an out of range voltage on either of the rear ABS 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/ETS is disabled, and the amber ABS warning indicator is turned on. The red BRAKE warning indicator is turned on if the rear piston in the ABS brake motor pack is not in the home position.

CONDITIONS FOR CLEARING DTC
Condition for DTC is no longer present and the scan tool (CLEAR DTCs) function is used, or 100 drive cycles have passed with no DTC(s) detected.

DIAGNOSTIC AIDS
Using the scan tool, select manual control function, and exercise ABS motor movement of the 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 ABS motor, an intermittent malfunction may be indicated. An intermittent malfunction may be 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 resets. 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.

NOTE: J 39200 test leads must be zeroed prior to making any resistance measurements. Refer to J 39200 user's manual.

After diagnosis is complete, clear the DTCs and test drive the vehicle for three drive cycles to verify that the DTC does not reset. A drive cycle consists of starting the vehicle, driving the vehicle over 16 km/h (10 mph), stopping, and then turning the ignition to off.