GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The seat adjuster switches are inputs to the driver seat module. The seat module supplies the adjuster switch assembly with a battery positive switch supply circuit and monitors the switch signal circuits. When a switch is pressed, the signal circuit is closed to the switch power circuit within the adjuster switch assembly. When battery voltage is present on the switch signal circuit, the seat module determines the switch status to be active.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC B1735 Driver Seat Front Up Switch Circuit
    • DTC B1740 Driver Seat Front Down Switch Circuit
    • DTC B1745 Driver Seat Rear Up Switch Circuit
    • DTC B1750 Driver Seat Rear Down Switch Circuit
    • DTC B1755 Driver Seat Forward Switch Circuit
    • DTC B1760 Driver Seat Rearward Switch Circuit

Conditions for Running the DTC

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

Conditions for Setting the DTC

A switch signal circuit to the seat module is active for more than 60 seconds.

Action Taken When the DTC Sets

The seat module will disable the seat adjuster function for which the DTC has set.

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.

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

Yes

No

Schematic Reference: Driver Seat Schematics

Connector End View Reference: Power Seat 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 switch parameter for which the DTC has set in the driver seat module Input/Output data list.

Does the scan tool display Inactive?

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

Go to Step 3

3

Disconnect the seat adjuster switch connector.

Does the scan tool display Inactive?

Go to Step 5

Go to Step 4

4

Test the switch signal circuit for which the DTC has set 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 9

Go to Step 7

5

Inspect for poor connections at the seat adjuster 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 9

Go to Step 6

6

Replace the seat adjuster switch. Refer to Power Seat Switch Replacement .

Is the repair complete?

Go to Step 9

--

7

Inspect for poor connections at the driver seat module (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 9

Go to Step 8

8

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

Is the repair complete?

Go to Step 9

--

9

  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