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Test I





Pinpoint Test I: DTC C1285-Booster Solenoid Circuit Failure


























CAUTION: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.


Normal Operation
The active brake booster has internal solenoids that assist driver brake applications or can apply the brakes when speeded if the vehicle loses control.
Power is supplied by circuit 1582 (LG/RD). Ground is provided through circuit 1583 (BK/WH).

Possible Causes
- circuit 1582 (LG/RD) open, short to power or ground
- circuit 1583 (BK/WH) open, short to power or ground
- Active brake booster
- ABS module