GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Warning: When using an external power source to provide power to a component or circuit, always use a fused jumper wire with the proper amp rating for the component or circuit being tested. Failure to use a fused jumper wire may result in accidental overload and may cause personal injury or damage to the component or circuit.

1

Visually and physically inspect for proper connections at the following connectors:

    • The 4-pin connector under the driver seat
    • The connector to the power driver seat switch

Were the connectors firmly attached?

--

Go to Step 3

Go to Step 2

2

  1. Properly connect the connectors.
  2. Attempt to adjust the power driver seat.

Does the power driver seat work after the connectors were correctly attached?

--

System OK

Go to Step 3

3

Attempt to adjust the power driver seat in each of the 3 directions: frontward/backward, front height, rear height.

Does the seat adjust in any direction?

--

Go to Step 8

Go to Step 4

4

  1. Disconnect the 4-pin connector from the body wiring harness which is found under the driver seat.
  2. Turn the ignition ON.
  3. Measure the voltage at the OG/BK wire and the body harness side of the 4-pin connector.

Is the voltage within the specified range?

11-14 V

Go to Step 6

Go to Step 5

5

Repair the power supply to the OG/BK wire and EF28.

Is the repair complete?

--

System OK

--

6

Use an ohmmeter to measure the resistance between ground and the BK wire at the disconnected 4-pin connector, body harness side.

Is the voltage near the specified value?

0 Ω

Go to Step 8

Go to Step 7

7

Repair the open BK wire between ground and the 4-pin body harness connector under the driver seat.

Is the repair complete?

--

System OK

--

8

Attempt to adjust the power driver seat forward and backward.

Does the power driver seat move forward and backward?

--

Go to Step 14

Go to Step 9

9

  1. Disconnect the power driver seat switch electrical connector.
  2. Move a vehicle battery near enough to the power driver seat switch so that the jumper wires can reach from the battery to the switch.
  3. Connect a jumper wire between the test battery negative terminal and the wire at terminal 3 on the motor side of the power driver seat switch.
  4. Carefully connect a fused jumper wire between the test battery positive terminal and the wire at terminal 4 on the motor side of the power driver seat switch. The 2 terminals are close together, and the motor may have a short circuit, so a fused jumper wire is recommended. Do not allow the wires from the battery to touch each other. If the motor is okay and it is not at the end of its travel, the power driver seat should move.
  5. To enable the motor to operate in the opposite direction, carefully reverse the battery connections.

Does the motor run backward and forward when the motor was directly powered by a vehicle battery?

--

Go to Step 10

Go to Step 11

10

  1. Replace the power driver seat switch.
  2. The power driver seat switch can be installed backward, so test the switch to verify that it is installed correctly before reinstalling the front power driver seat trim and switch.
  3. Install the front power driver seat trim.

Is the repair complete?

--

System OK

--

11

  1. Disconnect the 2-pin connector that joins the wires from the power driver seat switch to the forward/backward motor.
  2. Use an ohmmeter to measure the resistance of the wires between the power driver seat switch connector and the forward/backward motor connector.

Is the resistance of each wire near the specified value?

0 Ω

Go to Step 13

Go to Step 12

12

Repair the open circuit in the wire.

Is the repair complete?

--

System OK

--

13

Replace the power driver seat motor assembly.

Is the repair complete?

--

System OK

--

14

Attempt to adjust the power driver seat front height.

Does the front height adjustment work?

--

Go to Step 18

Go to Step 15

15

  1. Disconnect the power driver seat switch electrical connector.
  2. Move a vehicle battery near enough to the power driver seat switch so that jumper wires can reach from the battery to the switch.
  3. Connect a jumper wire between the test battery negative terminal and the wire at terminal 5 on the motor side of the power driver seat switch.
  4. Carefully connect a fused jumper wire between the test battery positive terminal and the wire at terminal 6 on the motor side of the power driver seat switch. The 2 terminals are close together, and the motor may have a short circuit, so a fused jumper wire is recommended. Do not allow the wires from the battery to touch each other. If the motor is good and it is not at the end of its travel, the power driver seat should move.
  5. To enable the motor to operate in the opposite direction, carefully reverse the battery connections.

Did the height adjust up and down when the motor was directly powered by a vehicle battery?

--

Go to Step 10

Go to Step 16

16

  1. Disconnect the 2-pin connector that joins the wires from the power driver seat switch to the front height motor.
  2. Use an ohmmeter to measure the resistance of the wires between the power driver seat switch connector and the front height motor connector.

Is the resistance of each wire near the specified value?

0 Ω

Go to Step 13

Go to Step 17

17

Repair the open circuit in the wires.

Is the repair complete?

--

System OK

--

18

Attempt to adjust the power driver seat rear height.

Does the rear height adjustment work?

--

Go to Step 22

Go to Step 19

19

  1. Disconnect the power driver seat switch electrical connector.
  2. Move a vehicle battery near enough to the power driver seat switch so that jumper wires can reach from the battery to the switch.
  3. Connect a jumper wire between the test battery negative terminal and the wire at terminal 7 on the motor side of the power driver seat switch.
  4. Carefully connect a fused jumper wire between the test battery positive terminal and the wire at terminal 8 on the motor side of the power driver seat switch. The 2 terminals are close together, and the motor may have a short circuit, so a fused jumper is recommended. Do not allow the wires from the battery to touch each other. If the motor is good and it is not at the end of its travel, the power driver seat should move.
  5. To enable the motor to operate in the opposite direction, carefully reverse the battery connection.

Did the height adjust up and down when the motor was directly powered by a vehicle battery?

--

Go to Step 10

Go to Step 20

20

  1. Disconnect the 2-pin connector that joins the wires from the power driver seat switch to the front height motor.
  2. Use an ohmmeter to measure the resistance of the wires between the power driver seat switch connector and the front height motor connector.

Is the resistance of each wire near the specified value?

0 Ω

Go to Step 13

Go to Step 21

21

Repair the open circuit in the wire.

Is the repair complete?

--

System OK

--

22

Attempt to adjust the power driver seat reclining.

Does the power driver seat recline?

--

System OK

Go to Step 23

23

  1. Disconnect the power driver seat switch electrical connector.
  2. Move a vehicle battery near enough to the power driver seat switch so that jumper wires can reach from the battery to the switch.
  3. Connect a jumper wire between the test battery negative terminal and the wire at terminal 9 on the motor side of the power driver seat switch.
  4. Carefully connect a fused jumper wire between the test battery positive terminal and the wire at terminal 10 on the motor side of the power driver seat switch. The 2 terminals are close together, and the motor may have a short circuit, so a fused jumper wire is recommended. Do not allow the wires from the battery to touch each other. If the motor is good and it is not at the end of its travel, the power driver seat should move.
  5. To enable the motor to operate in the opposite direction, carefully reverse the battery connections.

Did the height adjust up and down when the motor was directly powered by a vehicle battery?

--

Go to Step 10

Go to Step 24

24

  1. Disconnect the 2-pin connector that joins the wires from the power driver seat switch to the front height motor.
  2. Use an ohmmeter to measure the resistance of the wires between the power driver seat switch connector and the front height motor connector.

Is the resistance of each wire the specified value?

0 Ω

Go to Step 13

Go to Step 25

25

Repair the open circuit in the wire.

Is the repair complete?

--

System OK

--