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For 1990-2009 cars only

Adjustable Pedals Inoperative with AN3

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

12-Volt Reference

1

1

--

--

5-Volt Reference

B3606 01

B3606 06

B3606 06

--

Position Sensor Signal

B3606 06

B3606 06

B3606 06

--

Forward Switch Signal

2

2

B3604 01

--

Rearward Switch Signal

3

3

B3605 01

--

Motor Control A

1

1

1

--

Motor Control B

1

1

1

--

Low Reference

--

B3606 06

--

--

1. Adjustable Pedals Inoperative

2. Adjustable Pedals Forward Inoperative

3. Adjustable Pedals Rearward Inoperative

Circuit/System Description

The adjustable pedals assembly is moved forward or backward by a motor which is fixed to the brake pedal actuator with a drive cable to the accelerator pedal actuator. The memory seat module (MSM) controls the adjustable pedals motor by applying battery voltage to one of the outputs and ground to the other. The adjustable pedals motor is bidirectional and the direction of the pedal assembly travel is determined by which of the motor control circuits is switched to battery positive voltage while the other is grounded. The adjustable pedals forward and rearward switches are inputs to the MSM. The MSM supplies the switch assembly with a 12-volt reference. When the switch is operated to the forward or rearward direction, battery positive voltage is applied to the forward or rearward switch signal inputs.

Reference Information

Schematic Reference

Adjustable Pedal Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Adjustable Pedals Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Verify DTC B3604, B3605, or B3606 is not set.
  2. If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.
  3. Ignition ON, observe the scan tool Pedal Forward Switch and Pedal Aft Switch parameters while cycling the adjustable pedal switch between the FWD and RWD position. The appropriate parameter should change between Active and Inactive as commanded.
  4. If the parameters do not change between the specified values, refer to Adjustable Pedal Switch Circuit Malfunction.
  5. Verify the scan tool Pedal Position parameter is between 0.45-4.55 volts.
  6. If not within the specified range, refer to Adjustable Pedal Position Sensor Circuit Malfunction.
  7. Command the adjustable pedals to move forward and rearward. The pedals should move in the commanded direction.
  8. If the pedals do not move in the commanded direction, refer to Adjustable Pedal Motor Circuit Malfunction.

Circuit/System Testing

Adjustable Pedal Switch Circuit Malfunction

  1. Disconnect the harness connector at the adjustable pedal switch.
  2. Ignition ON, test for 11.8-12.2 volts between the appropriate 12-volt reference circuit listed below and ground:
  3. • X88/Z88 - terminal 11
    • Z75 - terminal 5
    If greater than the specified range, test the 12-volt reference circuit for a short to voltage. If the circuit tests normal, replace the MSM.
    If less than the specified range, test the 12-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
  4. Verify the scan tool Pedal Forward Switch parameter is Inactive.
  5. If not the specified value, test the appropriate signal circuit terminal listed below for a short to voltage. If the circuit tests normal, replace the MSM.
    • X88/Z88 - terminal 12
    • Z75 - terminal 6
  6. Verify the scan tool Pedal Aft Switch parameter is Inactive.
  7. If not the specified value, test the appropriate signal circuit terminal listed below for a short to voltage. If the circuit tests normal, replace the MSM.
    • X88/Z88 - terminal 10
    • Z75 - terminal 4
  8. Install a 3A fused jumper wire between the appropriate signal circuit terminal listed below and B+. The scan tool Pedal Forward Switch parameter should be Active.
  9. • X88/Z88 - terminal 12
    • Z75 - terminal 6
    If not the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
  10. Install a 3A fused jumper wire between the appropriate signal circuit terminal listed below and B+. The scan tool Pedal Aft Switch parameter should be Active.
  11. • X88/Z88 - terminal 10
    • Z75 - terminal 4
    If not the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
  12. If all circuits test normal, test or replace the adjustable pedal switch.

Adjustable Pedal Position Sensor Circuit Malfunction

  1. Ignition OFF, disconnect the harness connector at the adjustable pedal motor.
  2. Ignition OFF, test for less than 10 ohm between the low reference circuit terminal 3 and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the MSM.
  4. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 1 and ground.
  5. If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
    If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the MSM.
  6. Verify the scan tool Pedal Position parameter is less than 0.45 volt.
  7. If greater than the specified range, test the signal circuit terminal 2 for a short to voltage. If the circuit tests normal, replace the MSM.
  8. Install a 3A fused jumper wire between the signal circuit terminal 2 and the 5-volt reference circuit terminal 1. Verify the scan tool Pedal Position parameter is greater than 4.55 volts.
  9. If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
  10. If all circuits test normal, test or replace the adjustable pedal motor.

Adjustable Pedal Motor Circuit Malfunction

  1. Ignition OFF, disconnect the X3 harness connector at the MSM.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 5 and ground.
  3. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. Connect the X3 harness connector at the MSM and disconnect the harness connector at the electronic adjustable pedal assembly.
  5. Ignition ON, test for 1.5-2.5 volts between the control circuit terminals listed below and ground:
  6. • Control circuit terminal 4
    • Control circuit terminal 5
    If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the MSM.
    If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
  7. Connect the test lamp between the control circuit terminal 4 and the control circuit terminal 5.
  8. Command the adjustable pedals to move forward and rearward. The test lamp should illuminate each time the pedals are commanded to move.
  9. If the test lamp does not illuminate, replace the MSM.
  10. If all circuits test normal, test or replace the electronic adjustable pedal assembly.

Repair Instructions

Perform Diagnostic Repair Verification the after completing the diagnostic procedure.

    •  Accessory Switch Replacement
    •  Brake Pedal Assembly Replacement
    •  Control Module References for MSM replacement, setup, and programming

Adjustable Pedals Inoperative without AN3

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Park Enable Relay B+

2

2

--

--

Adjustable Pedal Switch B+

2

2

--

--

Forward Control

2

2

2

--

Rearward Control

2

2

2

--

Motor Control A

2

2

2

--

Motor Control B

2

2

2

--

Park Enable Relay Control

B3631 00

1

2

--

Park Enable Relay Ground

--

1

--

--

1. Adjustable Pedal Inhibit Inoperative

2. Adjustable Pedals Inoperative

Circuit/System Description

Voltage to the adjustable pedal switch is supplied through the park enable relay while in a de-energized state. The park enable relay is controlled by the body control module (BCM) through a high side drive control circuit and will be energized whenever the ignition is in the accessory, run, or crank positions and the transmission is in reverse or the cruise control is engaged. The adjustable pedals switch controls the adjustable pedals relay by applying battery voltage to one of the coils. In an inactive state both of the relay switch contacts are closed to ground and when one of the relay coils is energized its switch contact is closed to battery voltage.

Reference Information

Schematic Reference

Adjustable Pedal Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Adjustable Pedals Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Ignition ON, verify DTC B3631 is not set.
  2. If the DTC is set, refer to DTC B3631.
  3. Command the adjustable pedals to move forward and rearward. The pedals should move in the commanded direction.

Circuit/System Testing

  1. Ignition OFF, disconnect the X2 harness connector at the left IP junction block.
  2. Test for less than 10 ohms between the ground circuit terminal D1 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the test lamp illuminates between the B+ circuit terminal E2 and ground.
  5. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the circuit fuse is open, test the motor control circuits and the switch control circuits for a short to ground.
  6. Transmission in reverse, verify that a test lamp illuminates between the control circuit terminal E3 and ground.
  7. If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
  8. Ignition OFF, connect the X2 harness connector at the left IP junction block and disconnect the harness connector at the adjustable pedal switch.
  9. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 11 and ground.
  10. If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the left IP junction block.
  11. Ignition OFF, connect the harness connector at the adjustable pedal switch and disconnect the X2 harness at the left IP junction block.
  12. Ignition ON, verify a test lamp does not illuminate between the control circuit terminals listed below and ground:
  13. • Control circuit terminal E1
    • Control circuit terminal G1
    If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, test or replace the adjustable pedal switch.
  14. Adjustable pedal switch in the FWD position, verify a test lamp illuminates between the control circuit terminal G1 and ground.
  15. If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the adjustable pedal switch.
  16. Adjustable pedal switch in the RWD position, verify a test lamp illuminates between the control circuit terminal E1 and ground.
  17. If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the adjustable pedal switch.
  18. Ignition OFF, connect the X2 harness connector at the left IP junction block and disconnect the harness connector at the adjustable pedal assembly.
  19. Test for less than 10 ohms between the control circuit terminals listed below and ground:
  20. • Control circuit terminal 4
    • Control circuit terminal 5
    If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal, replace the left IP junction block.
  21. Ignition ON, verify a test lamp does not illuminate between the control circuit terminals listed below and ground:
  22. • Control circuit terminal 4
    • Control circuit terminal 5
    If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the left IP junction block.
  23. Adjustable pedal switch in the FWD position, verify a test lamp illuminates between the control circuit terminal 5 and ground.
  24. If the test lamp does not illuminate, test the control circuit for a short to ground. If the circuit tests normal, replace the left IP junction block.
  25. Adjustable pedal switch in the RWD position, verify a test lamp illuminates between the control circuit terminal 4 and ground.
  26. If the test lamp does not illuminate, test the control circuit for a short to ground. If the circuit tests normal, replace the left IP junction block.
  27. If all circuits test normal, test or replace the adjustable pedal assembly.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Accessory Switch Replacement
    •  Brake Pedal Assembly Replacement
    •  Instrument Panel Electrical Center or Junction Block Replacement - Left Side
    •  Control Module References for BCM replacement, setup, and programming