GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The driver seat adjuster motors are equipped with potentiometer type position sensors used by the driver seat module to determine the seat position. The position sensors are supplied with 5-volt reference and ground circuits from the driver seat module. The position sensor signal circuits are referenced from ground within the driver seat module. The signal circuit voltage levels monitored by the driver seat module range from 0.39-4.58 volts and are determined by the wiper locations on the resistors within the motor position sensors. The position sensor circuit voltage levels are used by the driver seat module to determine the seat position when storing or recalling memory position settings.

Conditions for Running the DTC

Battery voltage to the seat module must be within 8-17 volts.

Conditions for Setting the DTC

The position sensor signal circuit voltage level to the driver seat module is not within the 0.39-4.58 volt range.

Action Taken When the DTC Sets

The memory recall functions for the seat motor with a current status DTC will be disabled.

Conditions for Clearing the DTC

    • The DTC will be stored as a history code when the fault is no longer present.
    • A history DTC will be cleared after completing 100 consecutive ignition cycles, or by using the scan tool clearing DTCs feature.

Diagnostic Aids

If the DTC is only found in history, the fault may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Step

Action

Values

Yes

No

Schematic Reference: Memory Seats Schematics

Connector End View Reference: Power Seat Connector End Views

1

Did you perform the Power Seat Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Power Seat Systems

2

  1. Install a scan tool.
  2. With a scan tool, observe the appropriate position sensor parameter in the driver seat module Sensor Data list.

Is the position sensor parameter is 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

  1. Disconnect the position sensor connector.
  2. With a scan tool, observe the position sensor parameter.

Is the position sensor parameter less than the specified value?

0.39 V

Go to Step 4

Go to Step 8

4

  1. Connect a 3-amp fused jumper wire between the 5-volt reference circuit terminal and the signal circuit terminal in the position sensor harness connector.
  2. With a scan tool, observe the position sensor parameter.

Is the position sensor parameter is 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 low reference circuit terminal in the position sensor harness connector.

Is the voltage measure greater than the specified value?

5.0 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 to 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 to 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 of the position sensor for a short to voltage. 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 signal circuit of the position sensor for one of the following conditions:

    • A short to ground
    • A high resistance
    • 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

10

Test the low reference circuit of the position sensor for an open or high resistance. 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 11

11

Inspect for poor connections at the position sensor. 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 13

12

Inspect for poor connections at the seat 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

Replace the position sensor. Refer to Power Seat Adjuster Mechanism Replacement .

Did you complete the replacement?

--

Go to Step 15

--

14

Replace the driver seat module. Refer to Memory Seat Control Module Replacement .

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 as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK