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For 1990-2009 cars only

Power Seat Does Not Tilt 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 seat rear vertical up control circuit of the power seat switch with a test lamp that is connected to a good ground.
  2. Operate the seat rear vertical UP switch.

Does the test lamp illuminate?

--

Go to Step 3

Go to Step 5

3

  1. Probe the seat rear vertical down control circuit of the power seat switch with a test lamp that is connected to a good ground.
  2. Operate the power seat rear vertical DOWN switch .

Does the test lamp illuminate?

--

Go to Step 4

Go to Step 5

4

  1. Disconnect the seat rear vertical motor harness connector.
  2. Connect a test lamp between the up control circuit of the rear vertical motor and the down control circuit of the rear vertical motor.
  3. Operate the seat rear vertical switch in the UP and DOWN 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 harness connector of the seat rear vertical 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 rear vertical control circuits of the rear vertical 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 rear vertical 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 Tilt 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 Rear Up parameter in the Memory Seat Module data list.
  4. Activate the seat rear vertical UP switch.

Does the Seat Rear Up parameter change state?

--

Go to Step 3

Go to Step 5

3

Activate the seat rear vertical DOWN switch.

Does the Seat Rear Down parameter change state?

--

Go to Step 4

Go to Step 6

4

  1. Disconnect the seat rear vertical motor harness connector.
  2. Connect a test lamp between the rear vertical up control circuit of the rear vertical motor and the rear vertical down control circuit of the rear vertical motor.
  3. Operate the seat rear vertical switch in the UP and DOWN 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 rear vertical up signal circuit of the switch connector.

Does the Seat Rear Up 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 rear vertical down signal circuit of the switch connector.

Does the Seat Rear Down parameter change state?

--

Go to Step 12

Go to Step 10

7

Test the rear vertical up motor control circuit between the memory seat module and the rear vertical 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 rear vertical down motor control circuit between the memory seat module and the rear vertical 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 rear vertical up 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 rear vertical down 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 rear vertical 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 rear vertical 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