C1278

Part 1 Of 2:

Part 2 Of 2:

CIRCUIT DESCRIPTION
DTC C1278 identifies a brake solenoid valve that cannot be energized. The malfunction may be caused by one of the following conditions:
- An open in the solenoid valve circuitry
- The solenoid valve is always energized due to a short to ground in the solenoid valve circuitry between the driver and the brake solenoid valve.

An open will not allow proper ABS operation, but the short to ground simply turns on the brake solenoid valve. A path for base brakes is still allowed once the motor rehomes and the check ball is lifted off its seat during key to RUN initialization.

CONDITIONS FOR SETTING THE DTC
DTC C1278 can set only when the solenoid is commanded off while the Electronic Brake Control Relay is enabled.
A malfunction exists if the EBTCM detects the right front brake solenoid valve control circuit voltage is not within specifications.

ACTION TAKEN WHEN THE DTC SETS
- A malfunction DTC stores.
- The ABS/ETS disables.
- The amber ABS/ETS warning indicators 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 DTCs detected.

DIAGNOSTIC AIDS
If the malfunction is not current, use wiggle test on the wiring harness to pinpoint an intermittent malfunction in the motor circuitry or connections. Thoroughly inspect any circuitry that may be causing the intermittent complaint for the following conditions:
- Backed out terminals
- Improper mating
- Improperly formed or damaged terminals
- Poor terminal-to-wiring connections
- Physical damage to the wiring harness
- Rubbed-through wire insulation
- A broken wire inside the insulation