Brakes/Drivetrain - MIL/ABS Lamps ON/Possible DTC P0501
NUMBER: 08-048-05GROUP: Electrical
DATE: September 01, 2005
SUBJECT:
Rear Axle Fluid May Contaminate The Differential Mounted Rear Wheel Speed Sensor
OVERVIEW:
This bulletin involves the replacement of the differential mounted rear wheel speed sensor and the replacement of the rear axle fluid.
MODELS:
2005 (KJ) Liberty / Cherokee
SYMPTOM/CONDITION:
The customer may experience a brake/ABS warning light or a Malfunction Indicator Lamp (MIL) illumination. On vehicles equipped with an Anti-Lock Brake System (ABS), a Red brake light and/or an Amber ABS light may illuminate and remain on. On vehicles NOT equipped with ABS, the MIL may illuminate. The MIL may be due to DTC P0501 - Vehicle Speed Signal Performance / Vehicle Speed Sensor Plausibility.
The above condition may be due a rear differential mounted rear wheel speed sensor that may be contaminated by the rear axle fluid.
DIAGNOSIS:
Using the diagnostic Service Info procedures available on TechCONNECT, if proper diagnosis determines that the rear wheel speed sensor requires replacement, then perform the Repair Procedure.
PARTS REQUIRED:
REPAIR PROCEDURE:
1. Disconnect and isolate the negative battery cable from the battery.
2. Raise the vehicle on a suitable lift.
3. Remove the rear axle differential housing cover.
4. Thoroughly clean the axle, differential, and differential cover of old oil, debris, and RTV.
5. Remove the rear wheel speed sensor electrical connector. Remove the sensor from the axle.
6. Install the new 0-ring, p/n 05086373AA, to the new rear wheel speed sensor.
7. Lubricate the new rear wheel speed sensor and 0-ring
8. Install the new rear wheel speed sensor, p/n 56041393AA, to the axle. Tighten the attaching bolt to 9 Nm (80 in.lbs.).
9. Verify that the seal is securely in place between the sensor and wiring connector. Install the sensor electrical connector to the sensor.
10. Apply a bead of Axle RTV sealant, p/n 05013477AA, to the differential housing cover.
CAUTION:
If cover is not installed within 3 to 5 minutes of new RTV sealant application, the cover must be cleaned and new RTV sealant applied. Failure to follow instructions will cause a leak.
11. Install the cover and identification tag. Tighten cover bolts in a criss-cross pattern to 41 Nm (30 ft. lbs.).
12. If not already removed, remove the fill plug.
13. If axle is equipped with a Trac-Lok differential, install 4 oz. of Limited Slip Additive to the differential.
14. Fill the axle differential with the correct axle lubricant.
15. Install the fill plug.
16. Verify that the rear wheel speed sensor and differential housing cover is correctly installed.
17. Lower vehicle.
18. Connect the negative battery cable to the battery. Set the clock to the correct time.
POLICY:
Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:
FAILURE CODE:
Disclaimer:
This bulletin is supplied as technical information only and is not an authorization for repair.