Diagnostic Instructions

DTC Descriptors

DTC B3633 01: Pedals Horizontal Position Sensor Tracking Short to Battery

DTC B3633 06: Pedals Horizontal Position Sensor Tracking Short to Ground or Open

DTC B3633 5A: Pedals Horizontal Position Sensor Tracking Sensor Tracking Fault

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
5-Volt Reference	B1395 02, B1825 06, B1850 06, B2355 06, B2365 06, B2375 06, B3606 06, B3633 06	B3606 06	B1395 05, B1825 01, B1850 01, B2355 01, B2365 01, B2375 01, B3606 01, B3633 01	B3606 5A
Adjustable Accelerator Pedal Position Sensor Signal	B3633 06	B3633 06	B3633 01	B3633 5A
Adjustable Brake Pedal Position Sensor Signal	B3606 06	B3606 06	B3606 01	B3633 5A
Adjustable Pedals Motor Forward Control	B3920 02	B3606 61	B3920 01	B3606 5A
Adjustable Pedals Motor Rearward Control	B3920 02	B3606 61	B3920 01	B3606 5A
Memory Seat Sensor Low Reference	--	B3606 01, B3606 61, B3633 01	--	B3606 5A

Circuit/System Description

The memory seat module (MSM) monitors the locations of the adjustable pedals using position sensors mounted to the brake and accelerator pedal actuators. The position sensors are supplied with a 5-volt reference and ground circuits from the MSM. The position sensor signal circuits are referenced from ground within the MSM. The signal voltages monitored by the MSM range from 0.22-4.75 volts and are determined by the wiper locations on the resistors within the position sensors. The position sensor signal circuit voltage levels are used by the MSM to determine the positions of the adjustable pedals when storing or recalling memory position settings. The MSM also monitors the locations of both pedal assemblies in order to prevent a step over condition from occurring. During manual or memory operation the position sensor inputs to the MSM must remain within 0.1 volts or 33 counts of each other. During a calibration procedure the position sensor inputs must not vary more than 0.73 volts or 25 counts.

Conditions for Running the DTC

The MSM must be powered.

Conditions for Setting the DTC

B3633 01

The analog input from the accelerator pedal position sensor is greater than 4.75 volts, the sensor will be considered out of range and the MSM will set this DTC.

B3633 06

The analog input from the accelerator pedal position sensor is less than 0.22 volt , the sensor will be considered out of range and the MSM will set this DTC.

B3633 5A

During manual or memory operation the step over difference between the brake and accelerator pedal position sensor signals is greater than 0.1 volts or 33 counts.

Action Taken When the DTC Sets

Memory recall functions will be suspended.

Conditions for Clearing the DTC

Diagnostic Aids

The MSM may be referenced as the driver position module.

Reference Information

Schematic Reference

Connector End View Reference

Component Connector End Views

Description and Operation

Adjustable Pedals Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, observe the scan tool Memory Seat Module, Accelerator Pedal Position Sensor parameter. The readings should be between 1.5 volts and 3.4 volts and change while adjusting the pedals position.

Circuit/System Testing

B3633 01 and B3633 06

1. Ignition OFF, disconnect the X207 (LHD) or X203 (RHD) inline harness connector.
2. Ignition OFF, test for less than 7 ohms between the low reference circuit terminal listed below and ground:

•	Terminal 2 (LHD)

•	Terminal 4 (RHD)

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the MSM.

3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal listed below and ground:

•	Terminal 13 (LHD)

•	Terminal 7 (RHD)

⇒	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.

4. Ignition OFF, remove the 5-volt reference circuit terminal listed below from the MSM side of the connector:

•	Terminal 13 (LHD)

•	Terminal 7 (RHD)

5. Disconnect the X206 (LHD) or X201 (RHD) inline harness connector.
6. Remove the position sensor signal circuit terminal listed below from the MSM side of the connector:

•	Terminal 17 (LHD)

•	Terminal 18 (RHD)

7. Connect the inline harness connectors.
8. Ignition ON, verify the scan tool Adjustable Accelerator Pedal Sensor parameter is less than 0.45 volts.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the MSM.

9. Install a 3A fused jumper wire between the signal circuit and the 5-volt reference circuit. Verify the scan tool Adjustable Accelerator Pedal Sensor parameter is greater than 4.75 volts.

⇒	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. Test the accelerator pedal position sensor circuits between the inline harness connectors and the sensor for an open/high resistance, a short to ground, or a short to voltage.

⇒	If the circuits test normal, test or replace the adjustable accelerator pedal assembly.

B3633 5A

1. Ignition ON, verify that no other adjustable pedal DTCs are set.

⇒	If other adjustable pedal DTCs are set, diagnosis those DTCs first.

2. Disconnect the adjustable pedal drive cables from the motor.
3. Observe the scan tool Accelerator and Brake Pedal Position Sensor parameters while manually rotating the cables until the position sensor values are within 0.1 volts of each other.

⇒	If greater than the specified range, test or replace the appropriate cable or pedal assembly.

4. Perform the adjustable pedal calibration procedure. Refer to Adjustable Pedal System Calibration.
5. Verify the scan tool Accelerator and Brake Pedal Position Sensor parameter values are within 0.6 volts of each other.

⇒	If greater than the specified range, test or replace the appropriate cable or pedal assembly.

6. If all circuits/systems test normal, replace the MSM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.