GM Service Manual Online
For 1990-2009 cars only

Power Seat Does Not Tilt Rearward w/o Memory

Step

Action

Yes

No

Schematic Reference: Driver Seat Schematics and Passenger Seat Schematics

Connector End View Reference: Power Seat Connector End Views

1

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

Go to Step 2

Go to Symptoms - Seats

2

Verify the fault is present.

Does the system operate normally?

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

Go to Step 3

3

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

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

Go to Step 6

Go to Step 4

4

Test the rear vertical motor control circuits for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 5

5

Inspect for poor connections at the seat adjuster switch. 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 9

Go to Step 7

6

Inspect for poor connections at the rear vertical adjuster motor. 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 9

Go to Step 8

7

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

Is the repair complete?

Go to Step 9

--

8

Replace the rear vertical adjuster motor. Refer to Front Seat Adjuster Replacement .

Is the repair complete?

Go to Step 9

--

9

Operate the system to verify the repair.

Did you correct the condition?

System OK

Go to Step 3

Power Seat Does Not Tilt Rearward with 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 in Vehicle DTC Information

2

Verify the condition is present.

Does the system operate normally?

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

Go to Step 3

3

  1. Install a scan tool.
  2. Observe the Rear Vertical Up and Down Switch parameters in the driver seat module (DSM) Input/Output data list.

Do either of the Rear Vertical Switch parameters display Active?

Go to Step 4

Go to Step 5

4

Disconnect the seat adjuster switch connector.

Do both of the Rear Vertical Switch parameters display Inactive?

Go to Step 14

Go to Step 10

5

Operate the rear vertical up switch.

Does the scan tool display the rear vertical up switch as Active?

Go to Step 6

Go to Step 7

6

Operate the rear vertical down switch.

Does the scan tool display the rear vertical down switch as Active?

Go to Step 9

Go to Step 8

7

  1. Disconnect the seat adjuster switch connector.
  2. Connect a fused jumper wire from the battery voltage supply circuit terminal to the rear vertical up switch signal circuit terminal in the harness connector.

Does the scan tool display the rear vertical up switch as Active?

Go to Step 14

Go to Step 11

8

  1. Disconnect the seat adjuster switch connector.
  2. Connect a fused jumper wire from the battery voltage supply circuit terminal to the rear vertical down switch signal circuit terminal in the harness connector.

Does the scan tool display the rear vertical down switch as Active?

Go to Step 14

Go to Step 12

9

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

Does the test lamp illuminate when the switch is pressed in both directions?

Go to Step 16

Go to Step 13

10

Test the active rear vertical switch signal 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 20

Go to Step 15

11

Test the rear vertical up switch signal circuit 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 20

Go to Step 15

12

Test the rear vertical down switch signal circuit 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 20

Go to Step 15

13

Test the motor control circuits for an open or a high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 15

14

Inspect for poor connections at the seat adjuster switch harness connector. 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 20

Go to Step 17

15

Inspect for poor connections at the driver seat module (DSM) harness connectors. 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 20

Go to Step 18

16

Inspect for poor connections at the adjuster motor connector. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you fin and correct the condition?

Go to Step 20

Go to Step 19

17

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

Is the repair complete?

Go to Step 20

--

18

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

Is the repair complete?

Go to Step 20

--

19

Replace the inoperative adjuster motor. Refer to Front Seat Adjuster Motor Replacement .

Is the repair complete?

Go to Step 20

--

20

Operate the system to verify the repair.

Did you correct the condition?

System OK

Go to Step 3