GM Service Manual Online
For 1990-2009 cars only

Voltmeter Reading High/Low

Step

Action

Value(s)

Yes

No

1

Was the Charging System Check performed?

--

Go to Step  2

Go to Charging System Check

2

Start the vehicle.

Connect a DMMJ 39200 across the battery terminals.

Is the voltage reading within specification?

12.0 - 16.0  V

Go to Step 4

Go to Step  3

3

Inspect the generator. Refer to Generator Not Operating Properly .

Is the generator operating properly?

--

Go to Charging System Check

Go to Step 10

4

Compare the voltage reading at the battery to the voltage reading on the gauge in the Instrument Cluster.

Are the two readings within 1 volt?

--

Go to Charging System Check

Go to Step 4

5

  1. Disconnect Instrument Cluster.
  2. Connect a DMM J 39200 from CKT 39 (PNK ) to CKT 550 (BLK).

Is the reading within 1 volt of the reading at the battery?

--

Go to Step 6

Go to Step 7

6

Replace cluster link. Refer to Instrument Cluster Replacement in Instrument Panel Gauges and Console.

Is the repair complete?

--

Go to Charging System Check

--

7

Connect DMM J 39200 from CKT 550 (BLK) cavity B13 to Ground.

Is there high resistance?

--

Go to Step  8

Go to Step 9

8

Repair CKT 550 between Instrument Cluster and ground.

Is the repair complete?

--

Go to Charging System Check

--

9

Repair CKT 39 (PNK) between I/P fuse block and instrument cluster.

Is the repair complete?

--

Go to Charging System Check

--

10

Replace the Generator. Refer to Generator Replacement .

Is the repair complete?

--

Go to Charging System Check

--