C1271

CIRCUIT DESCRIPTION
The Master Cylinder Isolation valve solenoid circuits are supplied with battery power when the ignition is in the RUN position. The Electronic Brake and Traction Control Module (EBTCM) controls the valve functions by grounding the circuit when necessary.

CONDITIONS FOR SETTING THE DTC
The EBTCM senses a discrepancy such as an open short to ground, or short to voltage in the circuit.

ACTION TAKEN WHEN THE DTC SETS
A malfunction Diagnostic Trouble Code (DTC) is stored, ABS/TCS is disabled and the ABS and TRACTION OFF Indicators are turned on.

CONDITIONS FOR CLEARING THE DTC
^ Condition for DTC is no longer present and scan tool clear DTC function is used.
^ Fifty ignition cycles have passed with no DTC(s) detected.

DIAGNOSTIC AIDS
Make sure the integrity of the connection between the EBTCM and the Brake Pressure Modulator Valve (BPMV) is secure, tight, and free from corrosion.

TEST DESCRIPTION
The numbers below refer to step numbers on the diagnostic table.
3. Checks the resistance value of the solenoid.
4. Checks for a short to ground in the BPMV.
7. Checks for an internal short to voltage.