GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Does the front vertical adjustment operate properly?

--

Go to Step 6

Go to Step 2

2

Does the rear vertical adjustment operate properly?

--

Go to Step 16

Go to Step 3

3

Check for a poor connection at the seat adjuster switch connector or the seat adjuster motor assembly connectors C2 and C3.

Is there a poor connection?

--

Go to Step 4

Go to Step 5

4

Repair the poor connection.

Is the repair complete?

--

Go to Step 25

--

5

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

Is the repair complete?

--

Go to Step 25

--

6

  1. Using a test light, backprobe between the seat rear vertical adjuster motor assembly connector C2 terminal A and ground.
  2. While observing the test light, press the seat adjuster switch to rear height down.

Did the test light come on?

--

Go to Step 7

Go to Step 12

7

  1. Using a test light, backprobe between the seat rear vertical adjuster motor assembly connector C2 terminal B and ground.
  2. While observing the test light, press and hold the seat adjuster switch to rear height up.

Did the test light come on?

--

Go to Step 8

Go to Step 14

8

  1. Using a test light, backprobe between the seat adjuster motor assembly connector C2 terminal A and terminal B.
  2. Press the seat adjuster switch to rear height down.
  3. Press the seat adjuster switch to rear height up.

Did the test light illuminate in both directions?

--

Go to Step 9

Go to Step 5

9

Check for a poor connection at the seat adjuster motor assembly connector C2 terminal A or terminal B.

Is there a poor connection at the seat adjuster motor assembly connector C2?

--

Go to Step 10

Go to Step 11

10

Repair the poor connection at the seat adjuster motor assembly connector C2.

Is the repair complete?

--

Go to Step 25

--

11

Replace the seat adjuster motor assembly. Refer to Front Seat Adjuster Motor Replacement for service procedure.

Is the repair complete?

--

Go to Step 25

--

12

Check for a poor connection or an open in circuit 283.

Is there a poor connection or open in circuit 283?

--

Go to Step 13

Go to Step 5

13

Repair poor connection or open in circuit 283.

Is the repair complete?

--

Go to Step 25

--

14

Check for a poor connection or an open in circuit 282.

Is there a poor connection or open in circuit 282?

--

Go to Step 15

Go to Step 5

15

Repair poor connection or open in circuit 282.

Is the repair complete?

--

Go to Step 25

--

16

  1. Using a test light, backprobe between the seat front vertical adjuster motor assembly connector C3 terminal A and ground.
  2. While observing the test light, press the seat adjuster switch to front height down.

Did the test light come on?

--

Go to Step 17

Go to Step 21

17

  1. Using a test light, backprobe between the seat front vertical adjuster motor assembly connector C3 terminal B and ground.
  2. While observing the test light, press and hold the seat adjuster switch to front height up.

Did the test light come on?

--

Go to Step 18

Go to Step 23

18

  1. Using a test light, backprobe between the seat adjuster motor assembly connector C3 terminal A and terminal B.
  2. Press the seat adjuster switch to front height down.
  3. Press the seat adjuster switch to front height up.

Did the test light illuminate in both directions?

--

Go to Step 19

Go to Step 5

19

Check for a poor connection at the seat adjuster motor assembly connector C3 terminal A or terminal B.

Is there a poor connection at the seat adjuster motor assembly connector C3?

--

Go to Step 20

Go to Step 11

20

Repair poor connection at the seat adjuster motor assembly connector C3.

Is the repair complete?

--

Go to Step 25

--

21

Check for a poor connection or an open in circuit 287.

Is there a poor connection or open in circuit 287?

--

Go to Step 22

Go to Step 5

22

Repair the poor connection or open in circuit 287.

Is the repair complete?

--

Go to Step 25

--

23

Check for a poor connection or an open in circuit 286.

Is there a poor connection or open in circuit 286?

--

Go to Step 24

Go to Step 5

24

Repair poor connection or open in circuit 286.

Is the repair complete?

--

Go to Step 25

--

25

Reconnect connectors/components removed.

Is the action complete?

--

Go to Diagnostic System Check - Power Seat Systems

--