Pinpoint Test G: DTC C1996
Anti-Lock Control - Non-Hybrid
Pinpoint Tests
Pinpoint Test G: DTC C1996
Normal Operation
The ABS module uses information received from several sensors (wheel speed sensors, steering wheel rotation sensor, stability traction/control system sensors) 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. The ABS module does not expect ESC/RSC(R) interaction to be needed for longer than 15 seconds at a time. If inputs that require ESC/RSC(R) interaction remain active for longer than 15 seconds, the ABS module will disable the ESC and RSC(R) systems and set DTC C1996.
- DTC C1996 (Active Yaw and/or Roll Control Disabled) - The ABS module monitors the stability event and is programmed to set DTC C1996 and disable the ESC system if the stability event lasts longer than 15 seconds.
This pinpoint test is intended to diagnose the following:
- Steering wheel rotation sensor
- Stability/traction control sensors
- Wheel speed sensors
- ABS module
PINPOINT TEST G: DTC C1996
-------------------------------------------------
G1 CHECK FOR ABS MODULE DTCs
- Review the DTCs retrieved during Inspection and Verification.
- Are any ABS module DTCs other than C1996 present?
Yes
REPAIR all other DTCs before repairing C1996. GO to the ABS Module DTC Chart. [1][2]Diagnostic Trouble Code Descriptions
No
GO to G2.
-------------------------------------------------
G2 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 49 km/h (30 mph).
- Enter the following diagnostic mode on the scan tool: Self Test - ABS Module .
- Are any ABS module DTCs present?
Yes
If only DTC C1996 is present, GO to G3.
If DTC C1996 is present along with other DTCs, REPAIR the other DTCs before repairing DTC C1996. GO to the ABS Module DTC Chart. [1][2]Diagnostic Trouble Code Descriptions
No
The condition is not present at this time.
-------------------------------------------------
G3 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?
Yes
GO to G8.
No
GO to G4.
-------------------------------------------------
G4 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 G5.
No
TIGHTEN the wheel speed sensor bolt to specification. REFER to Specifications. CLEAR the DTCs. REPEAT the self-test.
-------------------------------------------------
G5 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 G6.
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.
-------------------------------------------------
G6 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 G7.
No
INSTALL a new wheel speed sensor ring. REFER to Wheel Speed Sensor Ring - Front Wheel Speed Sensor Ring - Front or Wheel Speed Sensor Ring - Rear Wheel Speed Sensor Ring - Rear. CLEAR the DTCs. REPEAT the self-test.
-------------------------------------------------
G7 INSPECT THE WHEEL BEARING FOR DAMAGE AND LOOSENESS
- Verify that the wheel bearing has no end-play and is undamaged.
- Is the wheel bearing OK?
Yes
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.
No
INSTALL a new wheel bearing and wheel hub as necessary. REFER to Front Suspension &/or Steering Knuckle for front wheel hubs or Rear Suspension for rear wheel hubs. CLEAR the DTCs. REPEAT the self-test.
-------------------------------------------------
G8 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 G9.
No
GO to G12.
-------------------------------------------------
G9 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 G10.
No
GO to G12.
-------------------------------------------------
G10 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 G11.
No
GO to G12.
-------------------------------------------------
G11 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 G13.
No
GO to G12.
-------------------------------------------------
G12 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.
- After depowering the system, refer to Restraints Control Module (RCM) Removal and Installation in Restraint Systems. Adhere to all safety warnings in the procedure while inspecting the Restraints Control Module (RCM) for damage or incorrect mounting.
- Inspect the RCM installation and make sure that the nuts are fully seated and tightened correctly. Refer to Restraints Control Module (RCM) in Restraint Systems.
- Inspect the mounting surface for damage, corrosion or dirt.
- Is the RCM installed correctly and is the mounting surface clean and free from damage?
Yes
GO to G14.
No
REPAIR or INSTALL new as necessary. CLEAR the DTC. REPEAT the self-test.
-------------------------------------------------
G13 CHECK THE STEERING WHEEL ANGLE SENSOR POSITION (SWA_POS) PID
- NOTE: The steering wheel angle sensor information is sent to the ABS module from the Power Steering Control Module (PSCM) over the High Speed Controller Area Network (HS-CAN) bus.
- 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 G14.
No
REFER to Steering to continue diagnosis of the steering wheel angle sensor.
-------------------------------------------------
G14 CHECK FOR CORRECT ABS MODULE OPERATION
- Disconnect: ABS Module C155 .
- Check the connector for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect: ABS Module C155 .
- 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. REPOWER the SRS. REFER to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems. 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. REPOWER the SRS. REFER to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems. CLEAR the DTCs. REPEAT the self-test.
-------------------------------------------------