C0037:29
Anti-Lock Control
Pinpoint Test B: DTCs C0030:07; C0031:29, 2F, 64; C0033:07, C0034:29, 2F, 64; C0036:07: C0037:29, 2F, 64; C0039:07; C003A:29, 2F or C003A:64
Refer to Wiring Diagram Set 42, Vehicle Dynamic Systems for schematic and connector information Electrical Diagrams.
Normal Operation
The wheel speed sensor and wheel speed sensor ring/magnetic strip generate a square wave signal to the ABS module that is proportional to wheel speed. The ABS module compares wheel speed inputs from all wheel speed sensors to determine an impending wheel lockup.
This pinpoint test is intended to diagnose the following:
- Incorrect/mismatched tires
- Wheel bearing
- Wheel speed sensor ring
- Wheel speed sensor
- Wiring, terminals or connectors
- ABS module
PINPOINT TEST B : DTC C0030:07; C0031:29, 2F, 64; C0033:07; C0034:29, 2F, 64; C0036:07: C0037:29, 2F, 64; C0039:07; C003A:29, 2F or 64
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
B1 CHECK THE DTCs FROM THE SELF-TEST
- Review the DTCs retrieved and recorded during Inspection and Verification.
Are DTCs C0031:01; C0034:01; C0037:01 and/or C003A:01 present?
Yes
GO to Pinpoint Test D Pinpoint Test D: DTCs C0031:01; C0034:01; C0037:01, C003A:01, C0031:19, C0034:19, C0037:19 and C003A:19.
No
GO to B2.
B2 CHECK THE TIRES SIZE AND PRESSURE
- Verify that all tires and wheels are the same size and that the tire size and inflation pressures are correct as indicated on the Vehicle Certification (VC) label.
Are the wheels and tires OK?
Yes
GO to B3.
No
INSTALL the correct size tire or ADJUST tire pressure as necessary. CLEAR the DTCs. REPEAT the self-test.
B3 CHECK THE WHEEL SPEED SENSOR AND HARNESS FOR DAMAGE
- With the vehicle in NEUTRAL, position it on a hoist.
- NOTE: Examine the wheel speed sensor harness carefully with a good light source. Failure to verify damage in the wheel speed sensor wire can lead to unnecessary installation of a new component.
Inspect the wheel speed sensor and harness for abrasion, broken connector tabs or water intrusion.
Is the wheel speed sensor and harness OK?
Yes
GO to B4.
No
INSTALL a new wheel speed sensor. REFER to Wheel Speed Sensor - Front or Wheel Speed Sensor - Rear . CLEAR the DTCs. REPEAT the self-test.
B4 INSPECT THE WHEEL SPEED SENSOR MOUNTING
- Inspect the wheel speed sensor and fastener for looseness.
Are the wheel speed sensor and fastener tight?
Yes
GO to B5.
No
TIGHTEN the wheel speed sensor to specification. REFER to Specifications. CLEAR the DTCs. REPEAT the self-test.
B5 CHECK THE WHEEL SPEED SENSOR RINGS AND WHEEL BEARING MAGNETIC STRIPS FOR DAMAGE
- Inspect the rear wheel bearings for abnormal wear or roughness and for deformation or contamination of the seal and magnetic strip.
- Inspect the front wheel speed sensor rings for cracks, chips, missing teeth and similar damage.
Are the wheel bearing(s) and sensor ring(s) OK?
Yes
GO to B6.
No
INSTALL a new wheel bearing as necessary.
INSTALL a new halfshaft as necessary.
CLEAR the DTCs. REPEAT the self-test.
B6 CHECK THE HARNESS AND CONNECTORS
- Disconnect: Suspect Wheel Speed Sensor.
- Disconnect: ABS Module C135.
- Inspect the connectors (including any in-line connectors) for:
- corrosion
- loose or spread terminals
- loose or frayed wire connections at terminals
Were any concerns found?
Yes
REPAIR as necessary.
Refer to Wiring Diagram Set 5 for schematic and connector information Electrical Diagrams.
No
If a single wheel speed sensor DTC is present, INSTALL a new wheel speed sensor. REFER to Wheel Speed Sensor - Front or Wheel Speed Sensor - Rear . CLEAR the DTCs. REPEAT the self-test.
If more than 1 wheel speed sensor DTC is present, GO to B7.
B7 CHECK FOR CORRECT ABS MODULE OPERATION
- Disconnect: ABS Module C135.
- Check for:
- corrosion
- pushed-out pins
- spread terminals
- Connect: ABS Module C135.
- Make sure the connector is seated correctly, then operate the system and verify the concern is still present.
Is the concern still present?
Yes
For vehicles without adaptive cruise control, INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module . TEST the system for normal operation.
For vehicles with adaptive cruise control, INSTALL a new HCU (Hydraulic Control Unit). REFER to Hydraulic Control Unit (HCU) .
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.