P0500/0503 is set by the PCM when the VSS signal from the ABS module is missing. If the vehicle has DTC P0500/P0503 in the PCM, and the vehicle has ABS DTCs, check ground 105 and the ABS fuse (mini fuse #11). C1175
If the vehicle has only DTC C1175 in the ABS module it is most likely caused by a wiring concern or a faulty sensor.
Inspect the vehicle wiring for damage beginning at the rear wheel speed sensor connector and ending at the ABS module. Damage may be at any point in the wiring.
Inspect for pinched looms, frayed terminal connections, loose pins, etc.
Pay special attention to the wiring along the frame (especially if the vehicle has been modified from a body builder), and near the fuel tank.
The speed sensor wiring begins at the rear axle and is routed along the frame rail on the left side of the vehicle. It then branches off at C140 (gas C133), which is located beneath the master cylinder. The wiring then goes to C455 at the ABS module.
The wiring should not be loose, especially near the rear wheel speed sensor. Ensure that the wiring is properly retained and routed to eliminate intermittent speed signals.
NOTE: USE A ZIP TIE TO SECURE THE HARNESS TO THE SENSOR SO THE PORTION OF THE HARNESS THAT IS COMING OFF OF THE BRAKE CABLE IS SUPPORTED.
Repair wiring as necessary.
If no concerns are found in the wiring, replace the sensor.
C1175 AND C1236
If the vehicle has DTC C1236 AND C1175 in the ABS module, check the vehicle wiring per the C1175 procedure. If there is a hard or intermittent wiring fault, the current may at times be high or low causing a C1175. A wiring concern may also cause noise in the circuit that can be interpreted by the module as an erratic speed signal, which will set a the C1236.
If no wiring issue is found, follow the C1236 procedure. C1236
If the vehicle has DTC C1236 in the ABS module, a wiring concern may exist that is severe enough to interrupt the signal, but not severe enough to totally open/short the circuit. Inspect the sensor connector on the 14405 harness for signs of water trapped in the strain relief elbow, corrosion, or connector broken/cracked. Install a new pigtail if necessary (See Pigtail Installation Procedure).
Ensure that the harness is properly retained and routed to eliminate intermittent speed signals.
Add dielectric grease to the connector.
If only DTC C1236 exists, and it occurs only under acceleration or towing, check for loose carrier bolts.
If no wiring concerns are present check the tone ring through the wheel speed sensor bore for damage, and for proper gap between the tone ring and ring gear.
Use a feeler gage to confirm gap between tone ring and ring gear is no larger than 0.010". Check the gap at multiple locations around the tone ring.
If gap is larger than 0.010", remove the axle cover and use suitable punch/driver to carefully "tap" tone ring back against ring gear. Recheck with feeler gage.
Examine each tooth of the tone wheel for damage. Even a small nick can cause a C1236 (Figure 1).
Figure 1 - Article 06-7-6
If no tone wheel issues are found, replace the wheel speed sensor.
Pigtail Installation
Disconnect the battery.
Disconnect the damaged connector from the axle.
Cut wiring near the rear wheel sensor takeout from 14405 harness.
Splice in pigtail (pigtail includes heat shrink).
Cover heat shrink with tubing.
Route the two (2) retainers of the pigtail to park brake cable.
NOTE: USE A ZIP TIE TO SECURE THE HARNESS TO THE SENSOR SO THE PORTION OF THE HARNESS THAT IS COMING OFF OF THE BRAKE CABLE IS SUPPORTED.
Plug in connector to rear wheel sensor.
Check for functionality.
PART NUMBER PART NAME
5C3Z-14S411-AA Jumper (Pigtail)
-4B409- Tone Ring (Order Per Axle Tag Number)
XG-3-A Silicone Brake Caliper Grease and Dielectric Compound
6L3Z-9E731-A Sensor Assy
