Speed Wheel Sensor RF Coherency Fault
Table of contents
- Possible Causes
- How To Fix
- Tech Notes
- Cost To Diagnose
- When is the code detected
- Possible Symptoms
- Description
C1148 MERCURY Possible Causes
- ABS RF Wheel Speed Sensor / Wiring intermittently open/shorted
- Tone wheel cracked/slipping on hub/axle/CV shaft
- Faulty / intermittent connection at the Anti-Lock Brake Control Module (ABCM or EBCM)
- Faulty Anti-Lock Brake Control Module
How do I fix code C1148 MERCURY?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Tech Notes
- This is typically an electrical wiring connection issue being monitored by the manufacturer.
- It can occur if:
- – The right front hub bearing/brake rotor is bad.
- – Can also be set if scan tool software is not updated.
Cost of diagnosing the C1148 MERCURY code
The cost of diagnosing the C1148 MERCURY code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
When is the code detected
If the output from right front wheel speed sensor at any time doesn’t match the other speed sensors once vehicle speed reaches a predetermined amount (5-15 MPH), code C1148 is set in memory.
Possible Symptoms
- Anti-Lock Brake System (ABS) Warning Light ON
- Engine Light ON (or Service Engine Soon Warning Light)
C1148 MERCURY Description
When the driver stops too fast, and one or more wheels begin to lock up, the ABS system takes over. It sees the wheel or wheels slowing down too rapidly by way of wheel speed sensors. When this happens, it shuts off brake fluid to the wheel with the inlet valve/coil, and releases the pressure with an outlet valve/coil. The Wheel Speed Sensor RF is typically found on vehicles with 4 Wheel Anti-Lock Brakes. The ABS system checks to be sure that the sensor electrical circuit is ok every time the key is turned on and the ABS module is powered up. It checks it again once vehicle speed reaches a preset speed (usually 5-15 mph).If there is a problem with the sensor or if the signal from the sensor is erratic, the ABS module will communicate over a data bus to the instrument cluster to turn on the amber Anti-Lock Light and the Red Brake Warning Light, and ABS will be disabled. In this case, the module has checked the right front wheel speed sensor/wiring and found the circuit has an electrical problem. This sets a C1148 in memory.