FixVault

Possible Causes

POSSIBLE CAUSES
FAULTY HYDRAULIC ASSEMBLY (BPP AND BRAKE SIMULATOR SENSORS ARE INTERNAL)
FAULTY BRAKE SYSTEM MODULE (BSM)

The (U0121, U0129) Loss of Communication faults can set for any of the following: 

POSSIBLE CAUSES
BATTERY OR IGNITION SUPPLY TO BSM OPEN OR SHORTED TO GROUND
BSM GROUND CIRCUIT OPEN/HIGH RESISTANCE
BSM CAN BUS CIRCUITS SHORTED TO VOLTAGE
BSM CAN BUS CIRCUITS SHORTED TO GROUND
BSM CAN BUS CIRCUITS OPEN/HIGH RESISTANCE
FAULTY BRAKE SYSTEM CONTROL MODULE (BSCM)

The Wheel Speed Sensor faults can set for any of the following: 

POSSIBLE CAUSES
SNA OR ERROR MESSAGE FROM BSCM
WSS SIGNAL CIRCUITS SHORTED TO VOLTAGE
WSS SIGNAL CIRCUITS SHORTED TO GROUND
WSS SIGNAL CIRCUITS OPEN/HIGH RESISTANCE
WSS GROUND CIRCUIT OPEN/HIGH RESISTANCE
DAMAGED TONE WHEEL
FAULTY WHEEL SPEED SENSOR
FAULTY BRAKE SYSTEM CONTROL MODULE (BSCM)