GM Service Manual Online
For 1990-2009 cars only

Fuel Gauge Always Indicates Empty Single Tank, Diesel

Step

Action

Value(s)

Yes

No

1

Did you perform the Instrument Cluster System Check?

--

Go to Step 2

Go to Instrument Cluster System Check

2

  1. Disconnect the Fuel Tank Sender connector at the left side frame rail.
  2. Turn the ignition switch to the RUN position.

Does the fuel gauge read Full or higher?

--

Go to Step 6

Go to Step 3

3

Connect a J 39200 DMM (continuity) between cavities A & B of the fuel pump and sender connector.

Does the resistance read according to fuel level?

0 ohms Empty/90 ohms Full

Go to Step 4

Go to Step 6

4

  1. Connect the Fuel Tank Sender and Pump connector.
  2. Remove the I/P Cluster. Refer to Instrument Cluster Replacement
  3. Connect a J 39200 DMM (continuity) between pin 16 of the I/P Cluster connector and ground.

Does the resistance read according to fuel level?

0 ohms Empty/90 ohms Full

Go to Step 5

Go to Step 7

5

Replace the I/P Cluster. Refer to Instrument Cluster Replacement

Is the repair complete?

--

Go to Instrument Cluster System Check

--

6

Replace the Fuel Pump and Sender. Refer to Fuel Sender Assembly Replacement in Engine Controls.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

7

Locate and repair the open in CKT 30 (PPL) between the I/P Cluster and Fuel Pump and Sender. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

Fuel Gauge Always Indicates Empty Gas

Step

Action

Value(s)

Yes

No

Important:: Before performing the diagnostics below, perform a diagnostic circuit check and repair DTC's P0461, P0462, or P0463 pertaining to the fuel tank senders.

1

Did you perform the Instrument Cluster System Check?

--

Go to Step 2

Go to Instrument Cluster System Check

2

  1. Remove the IP Cluster.
  2. Disconnect Vehicle Control Module (VCM) connector C1.
  3. Connect a J 39200 DMM (continuity) between cavity 9 of VCM connector C1 and ground.

Is contintuity present?

--

Go to Step 3

Go to Step 4

3

Locate and repair the short to ground in CKT 30 (PPL) between VCM connector C1 and the IP Cluster. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

4

Replace the I/P Cluster. Refer to Instrument Cluster Replacement .

Is the repair complete?

--

Go to Instrument Cluster System Check

--

Fuel Gauge Always Indicates Empty Dual Tank, Diesel

Step

Action

Value(s)

Yes

No

1

Did you perform the Instrument Cluster System Check?

--

Go to Step 2

Go to Instrument Cluster System Check

2

  1. Disconnect the Fuel Pump Balance Module connector.
  2. Turn the ignition switch to the RUN position.

Does the Fuel Gauge read Full?

--

Go to Step 6

Go to Step 3

3

  1. Remove the I/P Cluster.
  2. Connect a J 39200 DMM (continuity) between cavity 16 of the I/P Cluster connector and cavity F of the Fuel Pump Balance Module connector.

Is continuity present?

--

Go to Step 4

Go to Step 5

4

Replace the I/P Cluster. Refer to Instrument Cluster Replacement .

Is the repair complete?

Go to Instrument Cluster System Check

--

5

Locate and repair the open in CKT 30 (PPL) between the I/P Cluster and the Fuel Pump Balance Module. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

6

Connect a J 39200 DMM (ohms) between cavities E and B, and cavities E and C of the Fuel Pump Balance Module connector.

Does the resistance equal the value given?

0ohms Empty/90ohms Full

Go to Step 10

Go to Step 7

7

  1. Disconnect the Fuel Pump and Sender(s) that has the faulty circuit(s).
  2. Connect a J 39200 DMM (ohms) between the pins of the, presumed faulty, Fuel Pump and Sender(s).

Does the resistance equal the value given?

0ohms Empty/90ohms Full

Go to Step 8

Go to Step 9

8

Locate and repair the open circuit(s) between the Fuel Pump Balance Module and the Fuel Sender(s). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

9

Replace the Fuel Pump and Sender(s). Refer to Fuel Sender Assembly Replacement in Engine Controls.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

10

Connect a J 39200 DMM (continuity) between cavity A of the two Fuel Gauge Sender connectors and ground.

Is continuity present in both circuits to ground?

--

Go to Step 11

Go to Step 12

11

Replace the Fuel Pump Balance Module.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

12

Locate and repair the open in CKT 451 (BLK/WHT) between the Fuel Sender and G104. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Instrument Cluster System Check

--