GM Service Manual Online
For 1990-2009 cars only

Step

Action

Values

Yes

No

1

Check fuse F12 and EF21.

Is fuse F12 and EF21 blown?

--

Go to Step 2

Go to Step 3

2

  1. Check for a short circuit and repair it, if necessary.
  2. Replace the blown fuse.

Is the repair complete?

--

System OK

--

3

  1. Turn the ignition ON.
  2. Check the voltage at fuse EF21 and F12.

Is the battery voltage equal to the specified value?

11-14 V

Go to Step 5

Go to Step 4

4

Repair the open power supply circuit to fuse F12 and EF21.

Is the repair complete?

--

System OK

--

5

  1. Remove the instrument cluster.
  2. Disconnect instrument cluster connectors C2 and B12
  3. Turn the ignition ON.

Is the battery voltage equal to the specified value?

11-14 V

Go to Step 7

Go to Step 6

6

Repair the open circuit between fuses EF21 and F12 and instrument cluster connectors B14, C4 and B10.

Is the repair complete?

--

System OK

--

7

Check the instrument cluster warning lamp bulbs.

Are the bulbs OK?

--

Go to Step 9

Go to Step 8

8

  1. Replace any warning lamp bulbs that were defective.
  2. Check the charging system to make sure the alternator is not overcharging.
  3. Repair the charging system, if necessary.

Is the repair complete?

--

System OK

--

9

Replace the instrument cluster.

Is the repair complete?

--

System OK

--