Test Description
The numbers below refer to the step numbers in the diagnostic table.
- 2: Lack of communication may be due to partial or total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
- 4: The symptom list in Symptoms will determine the correct diagnostic procedure to use.
| Step | Action | Yes | No |
|---|
| 1 | Install a scan tool. Does the scan tool power up? | Go to Step 2 | Go to Scan Tool Does Not Power Up in Data Link Communications |
| 2 | Turn ON the ignition with the engine OFF. Use the scan tool in order to establish communication with the following modules: Automatic Transfer Case (ATC) Truck Body Control Module (TBC) Electronic Brake Control Module (EBCM) Instrument Panel Cluster (IPC) Powertrain Control Module (PCM) Rear Wheel Steering Control Module Sensing and Diagnostic Module (SDM) Does the scan tool communicate with all of the control modules listed above? | Go to Step 3 | Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications |
| 3 | IMPORTANT: The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode. Access the class 2 Power Mode in the Diagnostic Circuit Check on the scan tool. Rotate the ignition switch through all positions while observing the Ignition Switch Power Mode parameter. Does the Ignition Switch parameter reading match the ignition switch position for all switch positions? | Go to Step 4 | Go to Power Mode Mismatch in Body Control System |
| 4 | Select the display DTCs function on the scan tool for the following control modules: Automatic Transfer Case (ATC) Truck Body Control Module (TBC) Electronic Brake Control Module (EBCM) Instrument Panel Cluster (IPC) Powertrain Control Module (PCM) Rear Wheel Steering Control Module Sensing and Diagnostic Module (SDM) Does the scan tool display any DTCs for the control modules listed above? | Go to Step 5 | Go to Symptoms - Rear Wheel Steering System |
| 5 | Does the scan tool display any DTCs that begin with a "U"? | Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications | Go to Step 6 |
| 6 | Does the scan tool display DTC B1000? | Go to Diagnostic Trouble Code (DTC) List in Body Control System | Go to Step 7 |
| 7 | Does the scan tool display DTC B1367, P0562, P0563, P0621, P0615, P0622, P1637, P1638? | Go to Diagnostic Trouble Code (DTC) List in Engine Electrical | Go to Diagnostic Trouble Code (DTC) List |
| IMPORTANT |
|---|
| The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode. |
Diagnostic System Check - Rear Wheel Steering
The numbers below refer to the step numbers on the diagnostic table.
- 2: The normal state of the switch is the state of the switch input before activation. The terminology used by the scan tool is OFF.
- 3: Tests for the proper operation of the switch in the normally open position.
- 4: Tests for the proper operation of the switch in the closed position.
- 8: Tests the 5-volt reference circuit for an open or a short to ground.
| Step | Action | Value | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views |
| 1 | Did you perform the Diagnostic System Check-Rear Wheel Steering? | | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | Install a scan tool. Turn the ignition switch to the ON position, with the engine OFF. Activate the rear wheel steer mode select switch. With a scan tool, observe the Rear Wheel Steer Mode Select Switch Data parameter. Does the parameter change? | ON/OFF | Go to Diagnostic Aids | Go to Step 3 |
| 3 | Turn the ignition switch to the OFF position. Disconnect the rear wheel steer mode select switch. Measure the resistance between the 5-volt reference circuit and the mode select switch signal circuit on the rear wheel steer mode select switch. Does the resistance measure within the specified parameter? | 1.8 kohms to 2.2 kohms | Go to Step 4 | Go to Step 14 |
| 4 | Depress the rear wheel steer mode select switch. Measure the resistance between the 5-volt reference circuit and the mode select switch signal circuit on this switch. Does the resistance measure within the specified parameter? | 450 ohms- 550 ohms | Go to Step 5 | Go to Step 14 |
| 5 | Turn the ignition to the ON position, with the engine OFF. Measure the voltage between the 5-volt reference circuit of the rear wheel steer mode select switch harness connector and a good ground. Is the voltage at the 5-volt reference circuit within the specified parameter? | 4.750 to 5.00 V | Go to Step 7 | Go to Step 6 |
| 6 | Is the voltage at the 5-volt reference circuit less than the specified parameter? | 4.75 to 5.00 V | Go to Step 8 | Go to Step 9 |
| 7 | Turn the ignition switch to the OFF position. Measure the resistance between the mode select switch signal circuit of the rear wheel steer mode select switch connector and a good ground. Is the resistance at the mode select switch signal circuit less than the specified parameter? | 1500 ohms | Go to Step 12 | Go to Step 10 |
| 8 | Test the 5-volt reference circuit of the rear wheel steer mode select switch for an open, or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 11 |
| 9 | Test the 5-volt reference circuit of the rear wheel steer mode select switch for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 11 |
| 10 | Test the mode select switch signal circuit of the rear wheel steer mode select switch for an open, high resistance or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 11 |
| 11 | Inspect for poor connections at the harness connector of the rear wheel steering control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 12 |
| 12 | Inspect for poor connections at the harness connector of the rear wheel steer mode select switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 13 |
| 13 | IMPORTANT: Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) Replace the rear wheel steering control module. Refer to Rear Wheel Steering Control Module Replacement Did you complete the replacement? | | Go to Step 15 | |
| 14 | Replace the rear wheel steer mode select switch. Refer to Rear Wheel Steering Mode Switch Replacement . Did you complete the replacement? | | Go to Step 15 | |
| 15 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) |
The numbers below refer to the step numbers on the diagnostic table.
- 3: Tests whether the condition is module, system, or condition related.
- 4: Tests whether the condition has been corrected or identified as specified in the supporting text.
- 5: Test for an open or short in the vehicle speed signal circuit of the rear wheel steering control module.
| Step | Action | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views |
| 1 | Did you perform the Diagnostic System Check-Rear Wheel Steering? | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, monitor the DTC Information for DTC C0000 in the rear wheel steering control module. Does the scan tool indicate that DTC C0000 is current? | Go to Step 3 | Go to Step 4 |
| 3 | With a scan tool, monitor the DTC Information for DTC P0608 in the IPC. Does the scan tool indicate that DTC P0608 is current? | You must repair this DTC first. Go to DTC P0608 | Go to Diagnostic Aids |
| 4 | Use the scan tool in order to clear the DTCs. IMPORTANT: Do not cycle the ignition. Operate the vehicle within normal operating conditions. Does the DTC reset? | Go to Step 5 | System OK |
| 5 | Test the vehicle speed signal circuit of the rear wheel steering control module for a short to ground, short to voltage or an open between PCM and the rear wheel steering control module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 8 | Go to Step 6 |
| 6 | Inspect for poor connections at the rear wheel steering control module harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs Did you find and correct the condition? | Go to Step 8 | Go to Step 7 |
| 7 | IMPORTANT: Perform the Learn Alignment procedure. Replace the rear wheel steering module. Refer to Rear Wheel Steering Control Module Replacement .Did you complete the replacement? | Go to Step 8 | |
| 8 | Use the scan tool in order to clear the DTCs. Operate the vehicle within normal operating conditions. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Do not cycle the ignition. |
| IMPORTANT |
|---|
| Perform the Learn Alignment procedure. |
The number below refers to the step number on the diagnostic table.
- 2: This step verifies there was an improper rear wheel steering alignment performed.
| Step | Action | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views |
| 1 | Did you perform the Diagnostic System Check-Rear Wheel Steering? | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | Install a scan tool. Turn the ignition switch to the ON position, with the engine OFF. With a scan tool, monitor the DTC Information for DTC C0253 in the rear wheel steering control module. Does the scan tool indicate that DTC C0253 is current? | Go to Step 3 | Go to Diagnostic Aids |
| 3 | With a scan tool, monitor the DTC Information for DTC C0455 in the rear wheel steering control module. Does the scan tool indicate that DTC C0455 is current? | Go to DTC C0455 | Go to Step 4 |
| 4 | With a scan tool, monitor the DTC Information for DTC C0522 in the rear wheel steering control module. Does the scan tool indicate that DTC C0522 is current? | Go to DTC C0522 | Go to Step 5 |
| 5 | With the scan tool, monitor the sensor data. Is the steering wheel sensor analog voltage within valid alignment range (which is within 2.0-3.0 volts) and also is the sensor feed voltage 5.00 volts? | Go to Step 6 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
| 6 | With the scan tool, monitor the sensor data. Is the steering wheel sensor marker pulse within valid alignment range, and the steering wheel sensor index switch points are between + or - 10° of center, is the steering wheel centered? | Go to Step 7 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
| 7 | Is the scan tool data parameter rear wheel centering 1 within 2.0-3.0 volts and rear wheel centering 2 within 2.0-3.0 volts? | Go to Step 8 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
| 8 | IMPORTANT: Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. Replace the rear wheel steering module. Refer to Rear Wheel Steering Control Module Replacement .Did you complete the replacement? | Go to Step 9 | |
| 9 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. |
The numbers below refer to the step numbers on the diagnostic table.
- 3: This step will help determine if the fault is in the analog or the digital portion of the SWPS.
- 4: This step determines if the condition is currently present.
- 6: This step will help determine if a short to voltage exists in any of the digital circuits. A short to voltage in any of these circuits will cause all parameters to remain high.
- 14: This step checks for proper voltage to the phase A and Phase B circuits at the sensor and for proper operation of the sensor.
- 15: This step checks for proper voltage to the marker pulse circuit of the sensor and for proper operation of the sensor.
- 17: This step checks for proper operation of the sensor circuits by testing the sensors ability to switch a voltage signal between high and low.
| Step | Action | Values | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views |
| 1 | Did you perform the Diagnostic System Check - Rear Wheel Steering? | | Go to Step 2 | Go to Diagnostic Starting Point - Rear Wheel Steering |
| 2 | Install a scan tool. Turn the ignition ON, with the engine OFF. With the scan tool, monitor the DTC information in the Rear Wheel Steering Control module. Does the information indicate the DTC C0455 is current? | | Go to Step 3 | Go to Step 4 |
| 3 | With the scan tool, monitor the DTC information in the BCM. Does the information indicate a DTC C0472 or C0473 is present? | | Go to DTC C0472 or C0473 | Go to Step 4 |
| 4 | Center the steering wheel. Turn OFF the ignition. Wait 10 seconds. Turn ON the ignition, with the engine OFF. Rotate the steering wheel 90 degrees left and right. Monitor the DTC information in the rear wheel steering control module. Does the DTC C0455 become current? | | Go to Step 5 | Go to Diagnostic Aids |
| 5 | IMPORTANT: Rotating the steering wheel in excess of 30 degrees from center in either direction will result in DTC C0455 becoming current. This will result in inaccurate data being displayed and will cause misdiagnosis. If this occurs, you must repeat steps 1 through 4 of the following procedure before monitoring the data parameters. Center the steering wheel. Turn OFF the ignition. Wait 10 seconds. Turn ON the ignition, with the engine OFF. Observe the steering wheel angle in the rear wheel steering data list. Move the steering wheel slowly back and forth over center. Does the steering wheel angle value change? | | Go to Step 13 | Go to Step 6 |
| 6 | IMPORTANT: If DTC C0455 becomes current during this step, you must repeat steps 1 through 4 of Step 5 before monitoring the data parameters. Using the scan tool, monitor the Phase A, Phase B, and Marker Pulse Data parameters.Do all parameters remain HIGH at all times with steering input? | | Go to Step 8 | Go to Step 7 |
| 7 | IMPORTANT: If DTC C0455 becomes current during this step, you must repeat steps 1 through 4 of Step 5 before monitoring the data parameters. Using the scan tool, monitor the Phase A and Phase B Data parameters.Does the Phase A or Phase B parameter remain HIGH at all times with steering input? | | Go to Step 11 | Go to Step 12 |
| 8 | Test the battery positive voltage circuit of the steering wheel position sensor (SWPS) for an open or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 22 | Go to Step 9 |
| 9 | Test the ground circuit of the SWPS for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 22 | Go to Step 10 |
| 10 | Test the Phase A, Phase B, and marker pulse circuits for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 22 | Go to Step 14 |
| 11 | Test the Phase A or Phase B circuit for an open circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct a condition? | | Go to Step 22 | Go to Step 14 |
| 12 | Test the Phase A or Phase B circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 22 | Go to Step 14 |
| 13 | Test the marker pulse circuit for an open or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 22 | Go to Step 15 |
| 14 | IMPORTANT: If DTC C0455 becomes current during this step, you must repeat steps 1 through 4 of Step 5 before performing the following test. With the ignition ON, use a DVOM to measure the voltage of the Phase A and Phase B circuits by back probing the circuits at the SWPS while slowly rotating the steering wheel back an forth over center.Does the voltage switch in the range specified? | 0.080-0.180 V to 10.5-12.0 V | Go to Step 19 | Go to Step 16 |
| 15 | IMPORTANT: If DTC C0455 becomes current during this step, you must repeat steps 1 through 4 of Step 5 before performing the following test. With the ignition ON, use a DVOM to measure the voltage of the marker pulse circuit by back probing the circuit at the SWPS while rotating the steering wheel from center to more than 10 degrees but less than 30 degrees.Does the voltage change from high on center to low at greater than 10 degrees rotation? | 10.5-12.0 V to 0.080-0.180 V | Go to Step 19 | Go to Step 16 |
| 16 | Does the voltage of a circuit tested in a previous step remain high at all times? | | Go to Step 18 | Go to Step 17 |
| 17 | Connect a DVOM positive lead to battery voltage. Connect the DVOM negative lead to the circuit that remained low in the preceding step by back probing the circuit at the SWPS. Move the steering wheel slowly back and forth over center. Does the voltage switch between high and low? | | Go to Step 19 | Go to Step 18 |
| 18 | Inspect for poor connections at the SWPS. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 22 | Go to Step 20 |
| 19 | Inspect for poor connections at the rear wheel steering control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 22 | Go to Step 21 |
| 20 | IMPORTANT: Perform the learn alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. Replace the SWPS. Refer to Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement in Steering Wheel and Column.Did you complete the replacement? | | Go to Step 22 | |
| 21 | IMPORTANT: Perform the learn alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) . Replace the rear wheel steering control module. Refer to Rear Wheel Steering Control Module Replacement .Did you complete the replacement? | | Go to Step 22 | |
| 22 | Use the scan tool to clear DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Rotating the steering wheel in excess of 30 degrees from center in either direction will result in DTC C0455 becoming current. This will result in inaccurate data being displayed and will cause misdiagnosis. If this occurs, you must repeat steps 1 through 4 of the following procedure before monitoring the data parameters. |
| IMPORTANT |
|---|
| If DTC C0455 becomes current during this step, you must repeat steps 1 through 4 of Step 5 before monitoring the data parameters. |
| IMPORTANT |
|---|
| If DTC C0455 becomes current during this step, you must repeat steps 1 through 4 of Step 5 before monitoring the data parameters. |
| IMPORTANT |
|---|
| If DTC C0455 becomes current during this step, you must repeat steps 1 through 4 of Step 5 before performing the following test. |
| IMPORTANT |
|---|
| If DTC C0455 becomes current during this step, you must repeat steps 1 through 4 of Step 5 before performing the following test. |
| IMPORTANT |
|---|
| Perform the learn alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. |
| IMPORTANT |
|---|
| Perform the learn alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) . |
The numbers below refer to the step numbers on the diagnostic table.
- 4: This step checks the 5-volt reference and signal circuits. It also checks the ability of the BCM to read the signal circuit.
- 5: This step checks the integrity of the low reference circuit.
- 10: This step tests for excessive voltage on the 5-volt reference circuit.
| Step | Action | Values | Yes | No |
|---|
| Schematic Reference: Body Control System Schematics in Body Control System Connector End View Reference: Rear Wheel Steering Connector End Views |
| 1 | Did you perform the Rear Wheel Steering Diagnostic System Check? | | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | Use the scan tool to clear the DTC. Start the engine. With the engine running, turn the steering wheel back and forth from lock to lock. Does the DTC reset? | | Go to Step 3 | Go to Diagnostic Aids |
| 3 | Turn the ignition OFF. Disconnect the steering wheel position sensor harness connector. Turn the ignition ON. Select the Body Control Module Data List on the scan tool. Observe the Analog SWPS Signal parameter on the scan tool. Does the scan tool indicate that the Steering Wheel Position Sensor Data parameter is less than specified value? | 0.15 V | Go to Step 4 | Go to Step 9 |
| 4 | Connect a 3-amp fused jumper wire between the steering wheel position 5-volt reference circuit and the analog steering signal circuit. Observe the Analog SWPS Signal parameter on the scan tool. Does the scan tool indicate that the Steering Wheel Position Sensor Data parameter is greater than specified value? | 4.75 V | Go to Step 5 | Go to Step 6 |
| 5 | Use a DMM to measure the voltage between the steering wheel position 5-volt reference circuit and the steering wheel position low reference circuit. Does the voltage measure greater than the specified value? | 4.75 V | Go to Step 10 | Go to Step 8 |
| 6 | Test the 5-volt reference circuit of the steering wheel position sensor for an open or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 7 |
| 7 | Test the signal circuit of the steering wheel position sensor for an open or a short to ground. Refer to Testing for Short to Ground and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 12 |
| 8 | Test the low reference circuit of the steering wheel position sensor for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 12 |
| 9 | Test the signal circuit of the steering wheel position sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 14 |
| 10 | Test the 5-volt reference circuit of the steering wheel position sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 11 |
| 11 | Inspect for poor connections at the harness connector of the steering wheel position sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 13 |
| 12 | Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 14 |
| 13 | IMPORTANT: Perform the learn alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) Replace the steering wheel position sensor. Refer to Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement in Steering Wheel and Column.Did you complete the replacement? | | Go to Step 15 | |
| 14 | IMPORTANT: Perform the setup procedure for the BCM. Replace the BCM. Refer to Body Control Module Replacement in Body Control Systems.Did you complete the replacement? | | Go to Step 15 | |
| 15 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the conditions for running the DTC as specified in the supporting text. Does the DTC reset? | | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the learn alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
The numbers below refer to the step numbers on the diagnostic table.
- 1: This step requires the technician to perform the diagnostic procedure for the control module.
- 2: The minimum high limit is the value of voltage above which the code will set. The maximum low limit is the value of voltage below which the code will set.
- 3: Test for the proper operation of the position 1 or position 2 circuit in the high voltage range. Use a connector test adaptor kit in order to jumper the connections between the rear position sensor and the harness connector.
- 4: Test for the proper operation of the position 1 or position 2 circuit in the high voltage range.
- 5: Test for short to ground in the 5 volt reference circuit.
| Step | Action | Values | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views |
| 1 | Did you perform the Diagnostic System Check-Rear Wheel Steering? | | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | Install a scan tool. Turn the ignition switch to the ON position, with the engine OFF. With a scan tool, observe the rear position sensor position 1 and the rear position sensor position 2 data parameters. Does the scan tool indicate that the position 1 and position 2 data parameter are within the specified range? | 0.25-4.75 V | Go to Diagnostic Aids | Go to Step 3 |
| 3 | Turn the ignition switch to the OFF position. Disconnect the rear position sensor. Jumper all of the circuits of the rear wheel position sensor to the harness connector of the rear position sensor using a connector test adaptor kit. Disconnect the position 1 and position 2 circuit. Turn the ignition switch to the ON position, with the engine OFF. With a scan tool, observe the position 1 and the position 2 data parameters. Does the scan tool indicate that the position 1 or position 2 data parameter is greater than the specified value? | 4.75 V | Go to Step 4 | Go to Step 8 |
| 4 | Turn the ignition switch to the ON position. with the engine OFF. Connect the position 1 and the position 2 circuits. Connect a 3 amp fused jumper wire between the sensor ground circuit of the rear position sensor and position 1 and position 2 of the rear position sensor. Turn the ignition switch to the ON position. With a scan tool, observe the position 1 and the position 2 data parameter. Does the scan tool indicate that the position 1 and/or the position 2 data parameter is less than the specified value? | 0.25 V | Go to Step 5 | Go to Step 9 |
| 5 | Turn the ignition switch to the OFF position. Disconnect the fused jumper wire. Connect a 3 amp fused jumper wire between the 5 volt reference circuit of the rear position sensor and position 1 and position 2 of the rear position sensor. Turn the ignition switch to the ON position. with the engine OFF. With a scan tool, observe the position 1 and the position 2 data parameter. Does the scan tool indicate that the position 1 and/or position 2 data parameter is greater than the specified value? | 4.75 V | Go to Step 7 | Go to Step 6 |
| 6 | Test the 5 Volt reference circuit of the rear position sensor for a short to ground or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 12 |
| 7 | Test the 5 volt reference circuit of the rear wheel position sensor for a short to voltage, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 11 |
| 8 | Test the position 1 and position 2 signal circuit of the rear wheel position sensor for a short to ground. Refer to Circuit Testing , and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 12 |
| 9 | Test the position 1 and position 2 signal circuit of the rear wheel position sensor for a short to voltage, a high resistance or a open. Refer to Circuit Testing , and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 10 |
| 10 | Test the ground circuit of the rear wheel position sensor for a high resistance or an open. Refer to Circuit Testing , and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 12 |
| 11 | Inspect for poor connections at the harness connector of the rear wheel position sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 13 |
| 12 | Inspect for poor connections at the harness connector of the rear wheel control module. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 15 | Go to Step 14 |
| 13 | IMPORTANT: Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. Replace the rear wheel position sensor. Refer to Rear Position Sensor Replacement .Did you complete the replacement? | | Go to Step 15 | |
| 14 | IMPORTANT: Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. Replace the rear wheel steering module. Refer to Rear Wheel Steering Control Module Replacement Did you complete the replacement? | | Go to Step 15 | |
| 15 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. |
| IMPORTANT |
|---|
| Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. |
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step helps the technician determine if the fault is current.
- 3: This step determines if the DTC is the result of an intermittent connection at the control module.
| Step | Action | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views |
| 1 | Did you perform the Diagnostic System Check-Rear Wheel Steering? | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | Install a scan tool. Turn the ignition switch to the ON position, with the engine ON. With a scan tool, monitor the DTC Information for DTC C0527 in the rear wheel steering control module. Does the scan tool indicate that DTC C0527 is current? | Go to Step 3 | Go to Diagnostic Aids |
| 3 | Inspect for poor connections at the harness connector of the rear wheel steering control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 7 | Go to Step 4 |
| 4 | IMPORTANT: If the wiring harness to the steering gear motor is damaged in any way, it MUST be replaced. You can only service the connectors and terminals. Inspect for poor connections at the harness connector of the rear wheel steering control module and the steering gear motor connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.Did you find and correct the condition? | Go to Step 7 | Go to Step 5 |
| 5 | Replace the steering gear motor assembly. Refer to Steering Gear Motor Assembly Replacement in Rear Wheel Steering. Use the scan tool in order to clear the DTCs. Operate the vehicle within normal operating conditions. Does the DTC reset? | Go to Step 6 | Go to Step 7 |
| 6 | IMPORTANT: Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. Replace the rear wheel steering module. Refer to Rear Wheel Steering Control Module Replacement Did you complete the replacement? | Go to Step 7 | |
| 7 | Use the scan tool in order to clear the DTCs. Operate the vehicle within normal operating conditions. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| If the wiring harness to the steering gear motor is damaged in any way, it MUST be replaced. You can only service the connectors and terminals. |
| IMPORTANT |
|---|
| Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. |
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step tests for the proper operation of the rear steering position sensor.
- 3: This step tests for the proper operation of the rear steering motor position sensor.
- 4: This step performs the diagnostic procedure for the rear steering position sensor.
- 5: This step performs the diagnostic procedure for the rear steering motor position sensor.
| Step | Action | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views |
| 1 | Did you perform the Diagnostic System Check-Rear Wheel Steering? | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | Install a scan tool. Turn the ignition switch to the ON position, with the engine ON. With a scan tool, select the Display DTC function on the scan tool. Does the scan tool display DTC C0522 along with DTC C0532? | Go to Step 4 | Go to Step 3 |
| 3 | Does the scan tool display DTC C0527 along with DTC C0532? | Go to Step 5 | Go to Step 6 |
| 4 | Perform the diagnostic procedure for DTC C0522. Refer to DTC C0522 . Did you find and correct the condition? | Go to Step 8 | Go to Step 6 |
| 5 | Perform the diagnostic procedure for DTC C0527. Refer to DTC C0527 . Did you find and correct the condition? | Go to Step 8 | Go to Step 6 |
| 6 | Inspect for poor connections at the rear wheel steering control module and the rear wheel position sensor and rear wheel steering motor connectors. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition ? | Go to Step 8 | Go to Step 7 |
| 7 | IMPORTANT: Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. Replace the rear wheel steering module. Refer to Rear Wheel Steering Control Module Replacement Did you complete the replacement? | Go to Step 8 | |
| 8 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. |
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step will help the technician determine if there is an intermittent connection at the harness connector of the rear wheel steering motor.
| Step | Action | Values | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views |
| 1 | Did you perform the Diagnostic System Check-Rear Wheel Steering? | | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | With a scan tool, monitor the DTC Information DTC C0538 in the rear wheel steering module. Does the scan tool indicate that DTC C0538 is current? | | Go to Step 3 | Go to Diagnostic Aids |
| 3 | Turn the ignition switch to the OFF position. Inspect for poor connections at the harness connector of the rear wheel steering control module for the rear wheel steering gear motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | | Go to Step 6 | Go to Step 4 |
| 4 | Replace the rear wheel steering motor. Refer to Steering Gear Motor Assembly Replacement . Turn the ignition switch to the ON position, with the engine OFF. Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | | Go to Step 5 | Go to Step 6 |
| 5 | IMPORTANT: Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. Replace the rear wheel steering module. Refer to Rear Wheel Steering Control Module Replacement Did you complete the replacement? | | Go to Step 6 | |
| 6 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) in Wheel Alignment. |
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step begins the procedure that will allow the technician to determine the components responsible for setting DTC C0543.
- 3: This step will help determine if there are objects caught in the rear wheels.
| Step | Action | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views |
| 1 | Did you perform the Diagnostic System Check-Rear Wheel Steering? | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | Install a scan tool. Turn the ignition switch to the ON position, with the engine ON. With a scan tool, select the Display DTC function. Does the scan tool display DTC C0543? | Go to Step 3 | Go to Diagnostic Aids |
| 3 | Turn the ignition switch to the OFF position. Inspect the rear wheels for objects that may cause obstruction and remove. Did you find and correct the condition? | Go to Step 4 | Go to Diagnostic Aids |
| 4 | Turn the ignition switch to the ON position, with the engine ON. Use a scan tool in order to clear the DTC. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 3 | System OK |
The numbers below refer to the step numbers in the diagnostic table.
- 2: This step verifies that there are no other lighting concerns.
- 3: This step will verify the operation of the mode lamps and the Rear Wheel Steering systems ability to change mode of operation.
| Step | Action | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views in Rear Wheel Steering |
| 1 | Did you perform the Rear Wheel Steering Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | Are all other lighting systems operating properly? | Go to Step 3 | Go to Diagnostic System Check - Lighting Systems |
| 3 | Turn the ignition switch to the ON position. Operate the rear wheel steering mode select switch while observing the mode indicator lamps. Do the indicators turn on/off as expected? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 4 |
| 4 | Disconnect the rear wheel steering mode select switch. Test for a ground signal at the affected indicator control circuit at the rear wheel steering mode select switch connector. Is a ground signal present? | Go to Step 5 | Go to Step 6 |
| 5 | Test the affected indicator control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 7 |
| 6 | Inspect for poor connections at the harness connector of the Rear Wheel Steering Mode Select switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 8 |
| 7 | Inspect for poor connections at the harness connector of the rear wheel steering control module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 9 |
| 8 | Replace the rear wheel steering mode select switch. Refer to Rear Wheel Steering Mode Switch Replacement . Did you complete the replacement? | Go to Step 10 | |
| 9 | IMPORTANT: Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) Replace the rear wheel steering control module. Refer to Rear Wheel Steering Control Module Replacement in Rear Wheel Steering.Did you complete the replacement? | Go to Step 10 | |
| 10 | Use the scan tool to clear any DTCs. Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
| IMPORTANT |
|---|
| Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) |
One or Multiple Rear Wheel Steering Mode Switch Indicators Always On
The numbers below refer to the step numbers in the diagnostic table.
- 2: This step verifies that there are no other lighting concerns
- 3: This step will verify the operation of the mode lamps and the Rear Wheel Steering systems ability to change mode of operation.
| Step | Action | Yes | No |
|---|
| Schematic Reference: Rear Wheel Steering Schematics Connector End View Reference: Rear Wheel Steering Connector End Views in Rear Wheel Steering. |
| 1 | Did you perform the Rear Wheel Steering Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Rear Wheel Steering |
| 2 | Are all other lighting systems operating properly? | Go to Step 3 | Go to Diagnostic System Check - Lighting Systems |
| 3 | Turn the ignition switch to the ON position. Operate the rear wheel steering mode select switch while observing the mode indicator lamps. Do the mode indicator lamps turn on/off as expected? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 4 |
| 4 | Disconnect the rear wheel steering mode select switch. Turn the ignition switch to the ON position. Using the scan tool, actuate the affected indicator control circuit. Test for a ground signal at the affected indicator control circuit at the rear wheel steering mode select switch connector. Is a ground signal present? | Go to Step 6 | Go to Step 5 |
| 5 | Test the affected indicator control circuit for an open, high resistance or short to voltage. Refer to Circuit Testing and Circuit Testing in Wiring Systems. Did you find and correct a condition? | Go to Step 11 | Go to Step 8 |
| 6 | Test the four wheel steering mode indicator LED dimming signal circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct a condition? | Go to Step 11 | Go to Step 7 |
| 7 | Inspect for poor connections at the harness connector of the four wheel steering mode select switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 9 |
| 8 | Inspect for poor connections at the harness connector of the rear wheel steering control module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 10 |
| 9 | Replace the rear wheel steering mode select switch. Refer to Rear Wheel Steering Mode Switch Replacement . Did you complete the replacement? | Go to Step 11 | |
| 10 | IMPORTANT: Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) Replace the rear wheel steering control module. Refer to Rear Wheel Steering Control Module Replacement in Rear Wheel Steering.Did you complete the replacement? | Go to Step 11 | |
| 11 | Use the scan tool to clear any DTCs. Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
| IMPORTANT |
|---|
| Perform the Learn Alignment procedure. Refer to Measuring Wheel Alignment (w/Rear Wheel Steering) Measuring Wheel Alignment (w/o Rear Wheel Steering) |
One or Multiple Rear Wheel Steering Mode Switch Indicators Inoperative
Rear Wheel Steering Description and Operation
Quadrasteer™ is a 4-wheel steering system that dramatically enhances low speed maneuverability, high speed stability, and towing capability. The system is an electrically powered rear wheel steering system comprised of the following components
- A steerable, solid rear axle
- A heavy duty wiring harness and fuse
- A programmable control module
- A power relay in the control module
- A rack and pinion style steering actuator mounted on the rear differential cover
- An electric motor assembly on top of the rear steering actuator
- Three hall effect switches in the motor assembly
- A shorting relay in the motor assembly
- A rear wheel position sensor located under a cover on the bottom of the actuator, below the motor assembly
- A steering wheel position sensor located at the base of the steering column
- A mode select switch on the dash
The rear wheel steering control module has these inputs
- Battery voltage
- Switched battery voltage
- Class 2 serial data
- Steering wheel position sensor analog signal, via class 2 message from the body control module (BCM)
- Steering wheel position sensor phase A
- Steering wheel position sensor phase B
- Steering wheel position sensor marker pulse
- Rear wheel position sensor position 1
- Rear wheel position sensor position 2
- Rear wheel steering motor hall sensor hall A
- Rear wheel steering motor hall sensor hall B
- Rear wheel steering motor hall sensor hall C
- Vehicle speed signal from the instrument panel cluster (IPC)
- Rear wheel steering mode switch signal
The rear wheel steering control module has these outputs
- Rear wheel steering module class 2 serial data
- Rear wheel steering motor phase A control
- Rear wheel steering motor phase B control
- Rear wheel steering motor phase C control
- Rear wheel steering motor shorting relay voltage
- Rear wheel steering mode select switch supply voltage
- 2-wheel steer mode indicator control
- 4-wheel steer mode indicator control
- 4-wheel steer tow mode indicator control
- Rear wheel position sensor 5-volt reference
- Rear wheel steering motor hall sensor 12-volt reference
- Steering wheel position sensor phase A, phase B, and marker pulse 12-volt reference
Separate connectors to the rear wheel steering control module are provided for the following 4 capacities
- Vehicle battery power
- The vehicle class 2, steering wheel position, mode select switch, speed sensor signals
- The motor phase power leads
- The motor hall sensors, shorting relay, and rear wheel position sensor signals
| IMPORTANT | Beginning with the 2003 model year, the rear wheel steering control module supports flash programming. Beginning with the 2004 model year, the combination yaw rate/lateral accelerometer sensor has been removed. |
The system operates in 3 principal modes, as follows
The control module allows the vehicle rear wheels to turn a maximum of 12 degrees left or right. When the vehicle is operated in reverse, the maximum rear wheel steering angle is 5 degrees left or right. When the vehicle is sitting still in the test mode the system will move a maximum of 5 degrees left or right.
| IMPORTANT | The rear wheel steering control module may shut down if the system is operated under very extreme conditions and becomes overheated. The Service 4 Wheel Steering message will not be displayed. Once the temperature decreases back to operating range, the rear wheel steering system will resume normal operation upon the next ignition cycle. |
