A078

DTC A078 Right Front Solenoid Circuit Open Or Shorted To Battery:

Circuit Description:
This DTC identifies a solenoid that cannot be energized due to an open in its circuitry, or a solenoid that is always energized due to a short to battery in its circuitry between the driver and the solenoid. An open will not allow proper ABS operation but the short to battery simply turns the solenoid on. A path for base brakes is still allowed once the motor rehomes and the check ball is lifted off its seat during initialization.

Failure Condition:
DTC AO78 can be set only when the solenoid is commanded off. If the EBCM detects an excessive voltage in the right front solenoid control circuit a malfunction exists.

Action Taken:
A DTC AO78 is stored, ABS is disabled and the "ABS" indicator is turned on.

Test Description:
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This checks for a short to voltage in the control circuitry of the solenoid.
2. This checks for an open in the control circuit of the solenoid.
3. This step checks the solenoid coil for proper resistance.
4. This step checks for an open in the solenoid ground circuit.
5. This step checks for a possible intermittent malfunction in the solenoid circuitry due to poor terminal contact.

Diagnostic Aids:
An "intermittent" malfunction may be 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 TECH 1.

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.