Possible Causes
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- Incorrectly mounted RCM
- Network communication concern
- Incomplete or incorrect stability control sensor calibration
- Wheels and tires
- Front suspension components
- Steering system components
- EPAS column (the PSCM is part of the column)
Harness Side
Harness Side
Harness Side
Harness Side
- LA1: DETERMINE OPTIONAL STEERING CONTENT
- Using OASIS or the HVBOM, determine if the vehicle is equipped with adaptive steering.
- Is the vehicle equipped with adaptive steering?
Yes No GO to PINPOINT TEST AJ. Go to LA2. - LA2: CHECK THE WHEELS AND TIRES
- Inspect the wheels and tires for any damage or excessive wear.
- Verify all wheels and tires are the same size and match the size indicated on the VC label.
- Verify the inflation pressure of all 4 tires is correct as indicated on the VC label.
- Are the wheels and tires OK?
Yes No Go to LA3. INSTALL the correct size wheel or tire as necessary.
ADJUST tire pressure as necessary. - LA3: CHECK THE FRONT SUSPENSION AND STEERING COMPONENTS
- With the transmission in NEUTRAL, position the vehicle on a hoist. Refer to Jacking and Lifting article.
- Inspect the front suspension and steering components for any obvious signs of damage or missing components.
- Are the front suspension and steering components OK?
Yes No Go to LA4. REPAIR or INSTALL new components as necessary. - LA4: CHECK FOR OTHER DTCS
- Ignition ON, engine OFF.
Carry out the ABS self-test.
Carry out the PSCM self-test.
Carry out the RCM self-test.
- Are any DTCs other than those listed in the Fault Trigger Conditions Table present in any module?
Yes No DIAGNOSE all other DTCs before diagnosing any ABS module C0051:xx DTCs.
For RCM DTCs.
REFER to diagnosis and testing in the Supplemental Restraint System article.
For PSCM module DTCs.
REFER to diagnosis and testing in the Power Steering article.
For ABS module DTCs.
REFER to the ABS module DTC chart.Go to LA5. - LA5: VERIFY STABILITY CONTROL SENSOR CALIBRATION NOTE: The vehicle must be on level ground and at a complete standstill during the ABS Calibration. Any vehicle movement results in false values for this test.
- Using a diagnostic scan tool, carry out the ABS Calibration routine. Follow the diagnostic scan tool directions.
- Put the ABS module in sleep mode by performing the following steps:
- With ALL doors closed, set the ignition from ON to OFF.
- Disconnect the diagnostic scan tool.
- Open the door, exit the vehicle and close the door.
- Wait a minimum of 90 seconds for the ABS module to enter sleep mode.
- Ignition ON, engine OFF.
- Test drive the vehicle above 20 km/h (12 mph) and make at least one left turn and one right turn.
Carry out the ABS self-test.
- Are any DTCs listed in the DTC Fault Trigger Conditions table present?
Yes No Go to LA6. The condition causing the concern is no longer present. The concern was most likely due to an incomplete calibration or a failed calibration of the stability control sensors. - LA6: CHECK THE ABS MODULE YAW RATE VALUE PID NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement results in false values for this test.
- Access the ABS and monitor the YAW_RATE (ANGV) PID.
- Access the ABS and monitor the YAW_RATE_C (ANGV) PID.
- Is the PID value between -0.5 and 0.5?
Yes No Go to LA7. Go to LA9. - LA7: CHECK THE ABS MODULE LATERAL ACCELERATION PID NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement results in false values for this test.
- Access the ABS and monitor the LAT_ACCL (ACC) PID.
- Is the PID value between -0.04 and 0.04?
Yes No Go to LA8. Go to LA9. - LA8: CHECK THE ABS MODULE LONGITUDINAL ACCELERATION SENSOR PID NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement results in false values for this test.
- Access the ABS and monitor the LONG_ACCL (ACC) PID.
- Access the ABS and monitor the LNGACC (ACC) PID.
- Is the PID value between -0.04 and 0.04?
Yes No DIAGNOSE the PSCM. REFER to Power Steering article. RETRIEVE and RECORD all PSCM DTCs. If there are no DTCs present, REFER to the Symptom Chart. Go to LA9. - LA9: CHECK THE RCM INSTALLATION AND MOUNTING SURFACE 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.
- Ignition OFF.
- Wait one minute.
- RCM_A connector disconnected. (C310A)
- RCM_B connector disconnected. (C310B)
- Inspect the RCM installation and make sure the fasteners are fully seated and tightened to specifications. REFER to Supplemental Restraint System article.
- Inspect the RCM mounting surface for damage, corrosion or dirt.
- Is the RCM installed correctly and is the mounting surface clean and free from damage?
Yes No CHECK OASIS for any applicable service articles: TSB, GSB, SSM or FSA.
If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions.
If no service articles address this concern, INSTALL a new RCM. REFER to Supplemental Restraint System article.CLEAN or REPAIR the mounting surface or REINSTALL the RCM as necessary. REFER to Supplemental Restraint System article.