GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Using a test light, backprobe between the horizontal seat adjuster motor assembly connector C1 terminal A and ground.
  2. While observing the test light, press and the driver seat adjuster switch to the FORWARD position.

Upon pressing FORWARD, did the test light come on?

--

Go to Step 2

Go to Step 7

2

  1. Using a test light, backprobe between the horizontal seat adjuster motor assembly connector C1 terminal B and ground.
  2. While observing the test light, press and hold the driver seat adjuster switch to the BACK position.

Upon pressing BACK, did the test light come on?

--

Go to Step 3

Go to Step 10

3

  1. Using a test light, backprobe between the seat adjuster motor assembly connector C1 terminal A and terminal B.
  2. While observing the test light, press momentarily the seat adjuster switch to the FORWARD position.
  3. While observing the test light, press the seat adjuster switch to the BACK position.

Did the test light illuminate in both directions?

--

Go to Step 4

Go to Step 9

4

Check for a poor connection at the driver seat adjuster motor assembly connector C1 terminal A or terminal B.

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

--

Go to Step 5

Go to Step 6

5

Repair the poor connection or open at the seat adjuster motor assembly connector C1.

Is the repair complete?

--

Go to Step 12

--

6

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

Is the repair complete?

--

Go to Step 12

--

7

Check for a poor connection or an open in circuit 285.

Is there a poor connection or open in circuit 285?

--

Go to Step 8

Go to Step 9

8

Repair poor connection open in circuit 285.

Is the repair complete?

--

Go to Step 12

--

9

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

Is the repair complete?

--

Go to Step 12

--

10

Check for a poor connection or an open in circuit 284.

Is there a poor connection or an open in circuit 284?

--

Go to Step 11

Go to Step 9

11

Repair poor connection or open in circuit 284.

Is the repair complete?

--

Go to Step 12

--

12

Reconnect connectors/components removed.

Is the action complete?

--

Go to Diagnostic System Check - Power Seat Systems

--