GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

1

Inspect the R/CMT REL fuse for an open.

Is the fuse open?

Go to Step 7

Go to Step 2

2

  1. Disconnect the park/neutral position switch connector C1.
  2. Using a test lamp, probe between the transaxle range switch harness connector C1 from terminal B and ground.

Does the test lamp illuminate?

Go to Step 3

Go to Step 6

3

Using a test lamp, probe between the transaxle range switch harness connector C1, between terminal B and terminal  F.

Does the test lamp illuminate?

Go to Step 5

Go to Step 4

4

Repair the poor connection or an open in circuit 24 between the transaxle range switch harness connector C1 terminal F and S405.

Has the repair been made?

Go to Backup Lamp System Check

--

5

Adjust/Replace the park/neutral position switch and cable. Refer to Park/Neutral Position Switch Adjustment in Automatic Transaxle.

Has the repair been made?

Go to Backup Lamp System Check

--

6

Repair the poor connection or an open in circuit 840.

Has the repair been made?

Go to Backup Lamp System Check

--

7

Repair a short to ground in circuit 840 or circuit 24.

Has the repair been made?

Go to Backup Lamp System Check

--