GM Service Manual Online
For 1990-2009 cars only

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

2

Operate the horizontal adjuster switch in the forward and rearward directions.

Does the horizontal adjuster motor operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Install a scan tool.
  2. Observe the Horizontal Position Switch parameter in the seat module Inputs/Outputs data list.
  3. Operate the horizontal adjuster switch in the forward direction.

Does the scan tool display the correct switch status parameter in relation to the actual switch position?

Go to Step 4

Go to Step 5

4

Operate the horizontal adjuster switch in the rearward direction.

Does the scan tool display the correct Switch Status parameter in relation to the actual switch position?

Go to Step 7

Go to Step 6

5

  1. Disconnect the seat adjuster switch connector.
  2. Connect a 3-amp fused jumper wire between the battery voltage supply circuit terminal and the horizontal forward switch signal circuit terminal in the harness connector.
  3. Observe the Horizontal Position Switch parameter in the seat module Inputs/Outputs data list.

Does the scan tool display the Horizontal switch status parameter as forward?

Go to Step 12

Go to Step 8

6

  1. Disconnect the seat adjuster switch connector.
  2. Connect a 3-amp fused jumper wire between the battery voltage supply circuit terminal and the horizontal rearward switch signal circuit terminal in the harness connector.
  3. Observe the Horizontal Position Switch parameter in the seat module Inputs/Outputs data list.

Does the scan tool display the Horizontal switch status parameter as rearward?

Go to Step 12

Go to Step 9

7

  1. Disconnect the horizontal adjuster motor control circuit connector.
  2. Connect a test lamp between the control circuit terminals in the harness connector.
  3. Operate the horizontal adjuster switch in both directions.

Does the test lamp illuminate in the forward and backward switch positions only?

Go to Step 11

Go to Step 10

8

Test the horizontal forward switch signal circuit for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs.

Did you find and correct the condition?

Go to Step 17

Go to Step 13

9

Test the horizontal rearward switch signal circuit for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs.

Did you find and correct the condition?

Go to Step 17

Go to Step 13

10

Test the horizontal adjuster motor control circuits for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs .

Did you find and correct the condition?

Go to Step 17

Go to Step 13

11

Inspect for poor connections at the horizontal adjuster motor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs.

Did you find and correct the condition?

Go to Step 17

Go to Step 14

12

Inspect for poor connections at the seat adjuster switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs.

Did you find and correct the condition?

Go to Step 17

Go to Step 15

13

Inspect for poor connections at the seat module. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs.

Did you find and correct the condition?

Go to Step 17

Go to Step 16

14

Replace the horizontal adjuster motor. Refer to Power Seat Adjuster Mechanism Replacement .

Is the repair complete?

Go to Step 17

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15

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

Is the repair complete?

Go to Step 17

--

16

Replace the seat module. Refer to Control Module References for replacement, setup, and programming.

Is the repair complete?

Go to Step 17

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17

Operate the system to verify the repair.

Did you correct the condition?

System OK

Go to Step 2