C1048-LEFT REAR WHEEL PRESSURE PHASE MONITORING
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 Causes |
| LEFT REAR TONE WHEEL/WHEEL BEARING |
| WHEEL SPEED SIGNALS SWAPPED |
| LEFT REAR WSS |
| ANTI-LOCK BRAKES MODULE |
Diagnostic Test
1. COMPARE WHEEL SPEED SENSOR SIGNALSWARNING: Ensure 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 Rear WSS speed differ from the other WSS speeds by 8 km/h (5 mph) or show NO speed?
Yes
- Go To 2
No
- Perform 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?
Yes
- Repair as necessary.
- Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).
No
- Go To 3
3. CHECK WHEEL SPEED SENSOR WIRING
Check the Anti-Lock Brakes Module and Wheel Speed Sensors harness connectors for incorrectly wired connectors.
Were any problems found?
Yes
- Repair as necessary.
- Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).
No
- Go To 4
4. LEFT REAR WHEEL SPEED SENSOR
Replace the Left Rear Wheel Speed Sensor in accordance with the Service Information.
Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).
CAUTION: Ensure brake capability is available before road testing.
Road test the vehicle over 40 km/h (25 mph).
NOTE: Vehicle must be driven above 40 km/h (25 mph) for set conditions to be meet.
With the scan tool, read ABS DTCs.
NOTE: 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 C1048–LEFT REAR WHEEL PRESSURE PHASE MONITORING reset?
Yes
- Replace the Anti-Lock Brakes Module in accordance with the Service Information.
- Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).
No
- Test Complete.