GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The driver seat module (DSM) monitors the location of the adjustable pedals using the brake pedal position (BPP) sensor. The BPP sensor is supplied with 5-volt reference and ground circuits from the DSM. The position sensor signal circuit is referenced from ground within the DSM. The signal voltage monitored by the DSM ranges from 0.39-4.58 volts and is determined by the wiper location on the resistor within the position sensor. The position sensor circuit voltage level is used by the DSM to determine the position of the adjustable pedals when storing or recalling memory position settings.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3606 Adjustable Foot Pedal Position Sensor Circuit

Conditions for Running the DTC

The system voltage must be between 9-16 volts.

Conditions for Setting the DTC

The BPP sensor signal circuit voltage level to the DSM is not within the 0.39-4.58 volt range.

Action Taken When the DTC Sets

The DSM will not store or recall electronic adjustable pedals (EAP) memory or exit position settings.

Conditions for Clearing the DTC

    • The DTC will be current for as long as the fault is present.
    • When the fault is no longer present the DTC will be a history status code.
    • The history DTC will be cleared after 100 error-free ignition cycles, or by using the scan tool clearing DTCs feature.

Diagnostic Aids

A short to voltage on a sensor signal circuit or an open ground may effect other sensors using a common 5-volt reference and ground circuits causing the following DTCs to set:

    • DTC B1825
    • DTC B2435
    • DTC B2440

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Tests for the proper operation of the signal circuit in the low voltage range.

  2. Tests for the proper operation of the signal circuit in the high voltage range.

  3. Tests for a short to voltage in the 5-volt reference circuit.

Step

Action

Values

Yes

No

Schematic Reference: Adjustable Pedal Schematics

Connector End View Reference: Adjustable Pedal Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Install a scan tool.
  2. Observe the Pedal Position parameter in the driver seat module (DSM) Sensor Data list.

Is the Pedal Position parameter within the specified range?

0.39-4.58 V

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Disconnect the brake pedal position (BPP) sensor connector.

Is the Pedal Position parameter less than the specified value?

0.39 V

Go to Step 4

Go to Step 8

4

Connect a 3-ampere fused jumper wire between the signal circuit terminal and the 5-volt reference circuit terminal in the position sensor harness connector.

Is the Pedal Position parameter greater than the specified value?

4.58 V

Go to Step 5

Go to Step 7

5

  1. Disconnect the fused jumper wire.
  2. Measure the voltage between the 5-volt reference circuit terminal and the signal circuit terminal in the position sensor harness connector.

Is the Pedal Position parameter greater than the specified value?

5 V

Go to Step 6

Go to Step 10

6

Test the 5-volt reference circuit 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 12

7

Test the 5-volt reference circuit for one of the following conditions:

    • A short to ground
    • A high resistance
    • 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 9

8

Test the signal circuit 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 12

9

Test the signal circuit for one of the following conditions:

    • A short to ground
    • A high resistance
    • 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

10

Test the low reference circuit 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 15

Go to Step 11

11

Inspect for poor connections at the harness connector of the BPP 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 DSM. 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

Replace the BPP sensor. Refer to Brake Pedal Position Sensor Replacement .

Did you complete the replacement?

--

Go to Step 15

--

14

Replace the DSM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 15

--

15

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC reset?

--

Go to Step 2

System OK