GM Service Manual Online
For 1990-2009 cars only

Power Seat Inoperative w/o Memory

Step

Action

Yes

No

Schematic Reference: Driver Seat Schematics , Passenger Seat Schematics

Connector End View Reference: Power Seat Connector End Views

DEFINITION: One or more of the power seat functions are inoperative.

1

Did you review the Power Seat System Description and Operation and perform the necessary inspections?

Go to Step 2

Go to

2

Attempt to operate all of the power seat adjuster motors through their full range of adjustment.

Do all of the power seat adjuster motors operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Are all the power seat adjuster motors inoperative?

Go to Step 4

Go to Step 6

4

  1. Disconnect the power seat switch connector.
  2. Connect a test lamp from the battery voltage supply circuit terminal in the harness connector to a good ground.

Does the test lamp illuminate?

Go to Step 5

Go to Step 8

5

Connect a test lamp from the battery voltage supply circuit terminal to the ground circuit terminal in the power seat switch harness connector.

Does the test lamp illuminate?

Go to Step 10

Go to Step 9

6

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

Does the test lamp illuminate while the switch is operated in both directions?

Go to Step 11

Go to Step 7

7

  1. Disconnect the power seat switch connector.
  2. Test the inoperative 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 14

Go to Step 10

8

Repair the battery voltage supply circuit to the power seat switch for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs .

Is the repair complete?

Go to Step 14

--

9

Repair the power seat switch ground circuit for an open or high resistance. Refer to Circuit Testing and to Wiring Repairs .

Is the repair complete?

Go to Step 14

--

10

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

Did you find and correct the condition?

Go to Step 14

Go to Step 12

11

Inspect for poor connections at the inoperative 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 14

Go to Step 13

12

Replace the power seat switch. Refer to Power Seat Switch Replacement or to Front Seat Lumbar Control Switch Replacement .

Is the repair complete?

Go to Step 14

--

13

Replace the inoperative seat adjuster motor. Refer to Power Seat Adjuster Mechanism Replacement or to Front Seat Lumbar Support Replacement .

Is the repair complete?

Go to Step 14

--

14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3

Power Seat Inoperative w/Memory

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

Attempt to operate all of the seat adjuster motors through their full range of adjustment.

Do all of the seat adjuster motors operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Install a scan tool.
  2. Observe the Seat Adjuster Switch parameters in the seat module Inputs/Outputs data list.
  3. Operate the seat adjuster switches in both directions.

Does the scan tool display the correct Switch Status parameters in relation to the actual switch positions?

Go to Step 5

Go to Step 4

4

  1. Disconnect the seat adjuster switch connector.
  2. Using a DMM test for battery voltage at the switch supply voltage circuit terminal in the harness connector.

Is battery voltage present on the switch supply voltage circuit?

Go to Step 8

Go to Step 6

5

  1. Disconnect the seat module connector C1.
  2. Connect a test lamp from the high current battery voltage supply circuit terminal in the harness connector to ground.

Does the test lamp illuminate?

Go to Step 9

Go to Step 7

6

Test the battery voltage supply circuit to the power seat switch for open or short to ground. Refer to Circuit Testing and to Wiring Repairs.

Did you find and correct the condition?

Go to Step 12

Go to Step 9

7

Repair the high current battery voltage supply circuit to the seat module for open or short to ground. Refer to Circuit Testing and to Wiring Repairs.

Is the repair complete?

Go to Step 12

--

8

Inspect for poor connections at the harness connector of the power seat switch. Refer to Testing for Intermittent Conditions and Poor Connections.

Did you find and correct the condition?

Go to Step 12

Go to Step 10

9

Inspect for poor connections at the harness connectors of the memory seat module (MSM). Refer to Testing for Intermittent Conditions and Poor Connections.

Did you find and correct the condition?

Go to Step 12

Go to Step 11

10

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

Is the repair complete?

Go to Step 12

--

11

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

Is the repair complete?

Go to Step 12

--

12

Operate the system to verify the repair.

Did you correct the condition?

System OK

Go to Step 2