For a complete wiring diagram Refer to Section 8W.When Monitored:During active ABS control.Set Condition:If the Anti-Lock Brakes Module detects a pressure reduction phase and the following pressure hold phase is too long.Possible CausesLEFT FRONT TONE WHEEL/BEARING DAMAGEDWHEEL SPEED SIGNALS SWAPPEDLEFT FRONT WSSANTI-LOCK BRAKES MODULE1. COMPARE WHEEL SPEED SENSOR SIGNALSEnsure brake capability is available before road testing.With the scan tool, monitor ALL the WSS speeds while an assistant drives the vehicle.Slowly accelerate as straight as possible from a stop to 40 km/h (25 mph).Does the Left Front WSS speed differ from the other WSS speeds by 8 km/h (5 mph) or show NO speed?YesGo To 2 NoPerform the ABS Intermittent Condition diagnostic procedure in this Section.Refer to the ABS-INTERMITTENT CONDITION TEST. (Refer to 5 - BRAKES - DIAGNOSIS AND TESTING) 2. INSPECT TONE WHEEL/BEARING Turn the ignition off.Visually inspect the tone wheel and bearing for damage.Check the tone wheel teeth for missing teeth, cracks, and looseness. The teeth must be perfectly square, not bent, or nicked. Check the wheel bearing for worn/looseness.Were any problems found?YesRepair as necessary.Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).NoGo To 33. CHECK WHEEL SPEED SENSOR WIRINGCheck the Anti-Lock Brakes Module and Wheel Speed Sensors harness connectors for incorrectly wired connectors.Were any problems found?YesRepair as necessary.Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).NoGo To 44. LEFT FRONT WHEEL SPEED SENSORReplace the Left Front Wheel Speed Sensor in accordance with the Service Information.Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).Ensure brake capability is available before road testing.Road test the vehicle over 40 km/h (25 mph).Vehicle must be driven above 40 km/h (25 mph) for set conditions to be met.With the scan tool, read ABS DTCs.The Anti-Lock Brake Module must sense ALL 4 wheels at 12 km/h (7.5 mph) before it will extinguish the ABS indicators.Did DTC C1046–LEFT FRONT WHEEL PRESSURE PHASE MONITORING reset?YesReplace the Anti-Lock Brakes Module in accordance with the Service Information.Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).NoTest Complete.