GM Service Manual Online
For 1990-2009 cars only

Power Seat Does Not Move Forward/Rearward w/o A45

Step

Action

Value(s)

Yes

No

1

Did you review the power seat system operation and perform the necessary inspection?

--

Go to Step 2

Go to Symptoms

2

  1. Probe the entire seat backward control circuit of the power seat switch with a test lamp that is connected to a good ground.
  2. Operate the entire seat BACKWARD switch.

Does the test lamp illuminate?

--

Go to Step 3

Go to Step 5

3

  1. Probe the entire seat forward control circuit of the power seat switch with a test lamp that is connected to a good ground.
  2. Operate the entire seat FORWARD switch.

Does the test lamp illuminate?

--

Go to Step 4

Go to Step 5

4

  1. Disconnect the seat horizontal motor harness connector.
  2. Connect a test lamp between the forward control circuit of the seat horizontal motor and the backward control circuit of the seat horizontal motor.
  3. Operate the entire seat horizontal switch in the FORWARD and REARWARD directions.

Does the test lamp illuminate in both directions?

--

Go to Step 6

Go to Step 7

5

Inspect for poor connections at the harness connector of the power seat 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 10

Go to Step 8

6

Inspect for poor connections at the seat horizontal motor. 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 10

Go to Step 9

7

Repair the open in the entire seat horizontal control circuits of the lumbar horizontal motor. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 10

--

8

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

Did you complete the replacement?

--

Go to Step 10

--

9

Replace the seat horizontal motor. Refer to Seat Adjuster Motor Replacement - Power .

Did you complete the replacement?

--

Go to Step 10

--

10

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2

Power Seat Does Not Move Forward/Rearward w/A45

Step

Action

Value(s)

Yes

No

1

Did you perform A Diagnostic System Check - Power Seats Systems?

--

Go to Step 2

Go to Diagnostic System Check - Power Seat Systems

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the Seat Forward parameter in the Memory Seat Module data list.
  4. Operate the entire seat horizontal switch in the FORWARD direction.

Does the Seat Forward parameter change state?

--

Go to Step 3

Go to Step 5

3

Operate the entire seat horizontal switch in the BACKWARD direction.

Does the Seat Backward parameter change state?

--

Go to Step 4

Go to Step 6

4

  1. Disconnect the seat horizontal motor harness connector.
  2. Connect a test lamp between the forward control circuit of the horizontal motor and the rearward control circuit of the horizontal motor.
  3. Operate the entire seat horizontal switch in the FORWARD and REARWARD directions.

Does the test lamp illuminate in both directions?

--

Go to Step 13

Go to Step 7

5

  1. Disconnect the power seat switch harness connector.
  2. Connect a 3 amp fused jumper wire from battery positive voltage (B+) to the entire seat forward signal circuit of the switch connector.

Does the Seat Forward parameter change state?

--

Go to Step 12

Go to Step 9

6

  1. Disconnect the power seat switch harness connector.
  2. Connect a 3 amp fused jumper wire from battery positive voltage (B+) to the entire seat backward signal circuit of the switch connector.

Does the Seat Backward parameter change state?

--

Go to Step 12

Go to Step 10

7

Test the entire seat forward motor control circuit between the memory seat module and the horizontal motor for a short to ground or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 8

8

Test the entire seat backward motor control circuit between the memory seat module and the horizontal motor for a short to ground or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 11

9

Test the entire seat forward signal circuit between the power seat switch and the memory seat module for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 11

10

Test the entire seat backward signal circuit between the power seat switch and the memory seat module for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 11

11

Inspect for poor connections at the harness connector of the memory seat module. 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 17

Go to Step 14

12

Inspect for poor connections at the harness connector of the power seat 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 17

Go to Step 15

13

Inspect for poor connections at the harness connector of the seat horizontal motor. 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 17

Go to Step 16

14

Replace the memory seat module (MSM). Refer to Memory Seat Control Module Replacement .

Did you complete the replacement?

--

Go to Step 17

--

15

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

Did you complete the replacement?

--

Go to Step 17

--

16

Replace the seat horizontal motor. Refer to Seat Adjuster Motor Replacement - Power .

Did you complete the replacement?

--

Go to Step 17

--

17

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2