Pinpoint Test J: DTCs C1963 And C1975
Anti-Lock Control
Pinpoint Tests
Pinpoint Test J: DTCs C1963 and C1975
Refer to Wiring Diagram Set 42, Vehicle Dynamic Systems for schematic and connector information. Diagrams By Number
Normal Operation
The ABS module uses information received from several sensors (wheel speed sensors, steering wheel rotation sensor, stability/traction control system sensors, etc.) to determine if vehicle stability, traction or roll warrants Electronic Stability Control (ESC) or Roll Stability Control (RSC(R)) interaction. If an event is going to occur, the ABS module will adjust brake torque at specific wheels and the PCM will reduce engine torque to make the vehicle more stable. Once the ABS module has determined that the stability event has been corrected, it will return brake and engine torque to normal and continue to monitor the vehicle.
- DTC C1963 (Stability Control Inhibit Warning) - Once every ignition-cycle the ABS module will determine the straight-ahead or center position of the steering wheel by monitoring the steering wheel rotation sensor while the vehicle is being driven. If the vehicle reaches a speed of 75 km/h (47 mph) or if 30 seconds has passed since the initial drive-off, without finding the center, DTC C1963 will set.
- DTC C1975 (IVD Plausibility Failure) - The ABS module compares the signals from the stability/traction control system sensors to other sensor inputs. If the stability/traction control system sensor signals do not compare with other ABS module inputs, DTC C1975 will set.
This pinpoint test is intended to diagnose the following:
- Steering wheel rotation sensor
- Stability/traction control sensors
- Wheel speed sensors
- ABS module
PINPOINT TEST J: DTCs C1963 AND C1975
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J1 CHECK FOR ABS MODULE DTCs
- Review the DTCs retrieved during Inspection and Verification.
- Are any ABS module DTCs other than C1963 or C1975 present?
Yes
REPAIR all other DTCs before repairing C1963 or C1975. GO to the ABS Module DTC Chart. [1][2]Diagnostic Trouble Code Descriptions
No
GO to J2.
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J2 CHECK RETURNING DTCs
- Connect the scan tool.
- Ignition ON.
- Using the scan tool, clear all ABS module DTCs.
- Cycle the ignition switch from RUN to OFF and back to RUN.
- Test drive the vehicle above 75 km/h (47 mph).
- Enter the following diagnostic mode on the scan tool: Self Test - ABS Module .
- Are any ABS module DTCs present?
Yes
If only DTC C1963 or C1975 are present, GO to J3.
If DTC C1963 or C1975 is present along with other DTCs, REPAIR the other DTCs before repairing DTC C1963 or C1975. GO to the ABS Module DTC Chart. [1][2]Diagnostic Trouble Code Descriptions
No
The condition is not present at this time. INSPECT the steering wheel rotation sensor and the slotted-wheel for cracks, looseness and foreign material. REPAIR or INSTALL new as necessary. CLEAR the DTCs. REPEAT the self-test.
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J3 CHECK THE WHEEL SPEED SENSOR PIDs
- Enter the following diagnostic mode on the scan tool: DataLogger - ABS Module .
- While driving the vehicle, have an assistant monitor the following wheel speed sensor PIDs:
- Left Front Wheel Speed Sensor (LF_WSPD)
- Right Front Wheel Speed Sensor (RF_WSPD)
- Left Rear Wheel Speed Sensor (LR_WSPD)
- Right Rear Wheel Speed Sensor (RR_WSPD)
- Do all the PIDs match the vehicle speed and match each other within 1-3 km/h (1-2 mph)?
Yes
GO to J8.
No
GO to J4.
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J4 INSPECT THE WHEEL SPEED SENSOR MOUNTING
- Ignition OFF.
- With the vehicle in NEUTRAL, position it on a hoist. Refer to Vehicle Jacking and Lifting.
- Verify the bolt of the suspect wheel speed sensor is tightened to specifications.
- Is the bolt tightened to specifications?
Yes
GO to J5.
No
TIGHTEN the wheel speed sensor bolt to specification. REFER to Specifications. CLEAR the DTCs. REPEAT the self-test.
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J5 INSPECT THE WHEEL SPEED SENSOR AND HARNESS FOR DAMAGE
- NOTE: Examine the wheel speed sensor harness carefully with a good light source. Failure to verify damage in the sensor harness can lead to unnecessary installation of a new component.
- Inspect the suspect wheel speed sensor and harness for cuts, broken tabs, broken casing or corrosion.
- Are the wheel speed sensor and harness OK?
Yes
GO to J6.
No
INSTALL a new wheel speed sensor. REFER to Wheel Speed Sensor - Front Wheel Speed Sensor - Front or Wheel Speed Sensor - Rear Wheel Speed Sensor - Rear. CLEAR the DTCs. REPEAT the self-test.
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J6 INSPECT THE WHEEL SPEED SENSOR RING FOR DAMAGE
- NOTE: Examine the wheel speed sensor ring carefully with a good light source. Failure to verify damage in the sensor ring can lead to unnecessary installation of a new component.
- Inspect the suspect wheel speed sensor ring for cracks, chips or missing teeth. Rotate the wheel to verify that no teeth are missing.
- Is the wheel speed sensor ring OK?
Yes
GO to J7.
No
If a front wheel speed sensor ring is not OK, INSTALL a new wheel hub assembly. REFER to Wheel Hub in Front Suspension &/or Steering Knuckle for Rear Wheel Drive (RWD) or Front Suspension &/or Steering Knuckle for Four-Wheel Drive (4WD).
If a rear wheel speed sensor ring is not OK, REFER to Wheel Speed Sensor Ring - Rear Wheel Speed Sensor Ring - Rear. CLEAR the DTCs. REPEAT the self-test.
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J7 CHECK THE ABS MODULE YAW RATE (YAW_RATE) PID
- NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement results in false values for this test.
- Monitor the YAW_RATE PID.
- Is the YAW_RATE PID value between -0.05 and 0.05?
Yes
GO to J8.
No
GO to J11.
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J8 CHECK THE ABS MODULE LATERAL ACCELERATION (LAT_ACCL) PID
- NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement results in false values for this test.
- Monitor the LAT_ACCL PID.
- Is the LAT_ACCL PID value between -0.007 and 0.007?
Yes
GO to J9.
No
GO to J11.
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J9 CHECK THE ABS MODULE LONGITUDINAL ACCELERATION (LONG_ACCL) PID
- NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement results in false values for this test.
- Monitor the LONG_ACCL PID.
- Is the LONG_ACCL PID value between -0.004 and 0.004?
Yes
GO to J10.
No
GO to J11.
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J10 CHECK THE ABS MODULE ROLL RATE (ROLL_RAT) PID
NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement will result in false values for this test.
- Monitor the ROLL_RAT PID.
- Is the ROLL_RAT PID value between -0.05 and 0.05?
Yes
GO to J12.
No
GO to J11.
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J11 CHECK THE RCM INSTALLATION AND MOUNTING SURFACE
- Ignition OFF.
- Depower the Supplemental Restraint System (SRS). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems.
- Inspect the Restraints Control Module (RCM) installation and make sure that the nuts are fully seated and tightened correctly. Refer to RCM in Restraint Systems.
- Inspect the mounting surface for damage, corrosion or foreign material.
- Is the RCM installed correctly and is the mounting surface clean and free from damage?
Yes
GO to J14.
No
REPAIR or INSTALL new as necessary. CLEAR the DTCs. REPEAT the self-test.
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J12 CHECK THE STEERING WHEEL ROTATION SENSOR POSITION (SWA_POS) PID
- Monitor the SWA_POS PID while rotating the steering wheel clockwise and counterclockwise very slowly, from lock to lock.
- Does the PID change in intervals of 4.5 degrees and show a 360 degree increase for each complete revolution of the steering wheel?
Yes
GO to J14.
No
GO to J13.
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J13 INSPECT THE STEERING WHEEL ROTATION SENSOR
- Inspect the steering wheel rotation sensor and tone ring installation and make sure that fasteners are fully seated and tightened correctly. Refer to Steering Wheel Rotation Sensor Service and Repair.
- Inspect the steering wheel rotation sensor tone ring for damage or foreign material.
- Is the steering wheel rotation sensor and tone ring installed incorrectly, clean and free from damage?
Yes
GO to J14.
No
REPAIR, CLEAN or INSTALL new as necessary. CLEAR the DTC. REPEAT the self-test.
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J14 CHECK FOR CORRECT ABS MODULE OPERATION
WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Reconnect all SRS components (if previously disconnected).
- If previously directed to depower the SRS, repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems.
- Disconnect: ABS Module C135 .
- Check the connector for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect: ABS Module C135 .
- Make sure the ABS module electrical connector is fully seated, then operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module Service and Repair. CLEAR the DTCs. REPEAT the self-test.
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.
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