For 1990-2009 cars

## Fuel Gage Inaccurate or Inoperative Buick

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. Turn the ignition switch to the RUN position.
2. Using a scan tool, inspect for Powertrain Control Module (PCM) diagnostic trouble codes (DTCs). Refer to Engine Controls in order to diagnose PCM DTCs.
3. Turn the ignition switch to the OFF position.
4. Disconnect the fuel tank unit connector.
5. Connect the 2 red leads from the J 33431-C to the harness connector terminal B and terminal D.
6. Turn the ignition switch to the RUN position.
7. Set the tester resistance dials to 40 ohms (EMPTY).
8. Set the tester resistance dials to 248 ohms (FULL).

Does the fuel gauge display E at 40 ohms and F at 248 ohms?

--

Go to Step 4

Go to Step 3

3 |

1. Disconnect the instrument cluster connector.
2. Connect a J 39200 Digital Multimeter (DMM) between the instrument cluster connector terminal B2 and terminal B6.
3. Set the tester resistance dials to 40 ohms.
4. Set the tester resistance dials to 248 ohms.

Does the J 39200 DMM voltage vary as the tester resistance changes?

--

Go to Step 6

Go to Step 5

4 |

1. Connect a scan tool.
2. Establish communications with the Powertrain Control Module (PCM).
3. Set the tester resistance dials to 40 ohms (EMPTY).
4. Set the tester resistance dials to 248 ohms (FULL).

Does the PCM see a change in the fuel level sender data?

--

Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls

Go to Step 8

5 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the PCM connector C2.
3. Connect a J 39200 DMM between terminal B2 and ground.

Does the J 39200 DMM display less than the specified value?

5 ohms

Go to Step 10

Go to Step 9

6 | Inspect the instrument cluster connector for proper terminal contact. Is the contact OK? | -- | Go to Step 7 | Go to Step 18
7 | Replace the instrument cluster.

• | For Buick only, refer to Instrument Cluster Replacement .

• | For Oldsmobile only, refer to Instrument Cluster Replacement .

• | For Pontiac only, refer to Instrument Cluster Replacement .

Is the replacement complete?

--

Go to Step 17

--

8 | Inspect for a short to voltage or short to ground in CKT 1589. Is the circuit OK? | -- | Go to Step 12 | Go to Step 11
9 | Connect a J 39200 DMM between the cluster connector terminal B2 and the PCM connector C2 terminal 3. Does the J 39200 DMM display less than the specified value? | 5 ohms | Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls | Go to Step 13
10 | Inspect CKT 455 (PPL/WHT) for a short to ground. Is the wiring OK? | -- | Go to Step 14 | Go to Step 14
11 | Repair the short to voltage or ground in CKT 1589. Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? | -- | Go to Step 17 | --
12 | Inspect CKT 808 for an open. Was a problem found on CKT 808? | -- | Go to Step 15 | Go to Step 16
13 | Repair the open in CKT 455 (PPL/WHT). Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? | -- | Go to Step 17 | --
14 | Repair CKT 455 (PPL/WHT) for a short to ground. Refer to Repairing Damaged Wire Insulation Is the repair complete? | -- | Go to Step 17 | --
15 | Repair the open in CKT 808. Refer to Repairing Damaged Wire Insulation . Is the repair complete? | -- | Go to Step 17 | --
16 | Replace the fuel level sender. Refer to Fuel Sender Assembly Replacement in Engine Controls. Is the replacement complete? | -- | Go to Step 17 | --
17 |

1. Ensure that any components that you removed during diagnosis are installed in place.
2. Ensure that all connectors are connected.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

18 | Repair the poor terminal contact. Is the repair complete? | -- | Go to Instrument Cluster System Check | --

## Fuel Gage Inaccurate or Inoperative Oldsmobile

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. Turn the ignition switch to the RUN position.
2. Using a scan tool, inspect for the Instrument Panel Cluster (IPC) diagnostic trouble codes (DTCs).

Does the scan tool display DTC B0028 fuel sender circuit?

--

Go to Step 4

Go to Step 3

3 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the fuel tank unit connector.
3. Connect the 2 red leads from the J 33431-C tester to terminal B (PPL) and terminal D (BLK).
4. Turn the ignition switch to the RUN position.
5. Set the tester resistance dials to 40 ohms (EMPTY).
6. Set the tester resistance dials to 248 ohms (FULL).

Does the fuel gauge display E at 40 ohms and F at 248 ohms?

--

Go to Step 8

Go to Step 9

4 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the fuel tank unit connector.
3. Connect the jumper fuel tank unit harness connector terminal B (PPL) to ground.
4. Turn the ignition switch to the RUN position.

Does the fuel gauge read EMPTY?

--

Go to Step 7

Go to Step 5

5 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the instrument cluster connector.
3. Inspect CKT 30 (PPL) for an open or for high resistance.

Is the wiring OK?

--

Go to Step 7

Go to Step 6

6 | Repair the open or the high resistance in CKT 30 (PPL). Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? | -- | Go to Step 7 | --
7 | Replace the instrument cluster. Refer to the appropriate procedure:

• | Instrument Cluster Replacement

• | Instrument Cluster Replacement

• | Instrument Cluster Replacement

Is the replacement complete?

--

Go to Step 16

--

8 |

1. Turn the ignition switch to the OFF position.
2. Inspect CKT 552 (BLK) for an open or for high resistance.

Is the wiring OK?

--

Go to Step 9

Go to Step 15

9 | Replace the fuel level sender. Refer to Fuel Sender Assembly Replacement in Engine Controls. Is the repair complete? | -- | Go to Step 16 | --
10 | Inspect CKT 30 (PPL) for a short to ground, an open or high resistance. Were any problems found with CKT 30 (PPL)? | -- | Go to Step 11 | Go to Step 12
11 | Repair open, short to ground or high resistance in CKT 30 (PPL). Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? |  | Go to Step 16 |
12 | Inspect CKT 552 (BLK) for an open or for high resistance. Is the wiring OK? | -- | Go to Step 13 | Go to Step 14
13 | Replace the instrument cluster. Refer to the appropriate procedure:

• | Instrument Cluster Replacement

• | Instrument Cluster Replacement

• | Instrument Cluster Replacement

Is the replacement complete?

--

Go to Step 16

--

14 | Repair CKT 552 (BLK) for open or high resistance. Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? | -- | Go to Step 16 | --
15 | Repair the open or high resistance in CKT 552 (BLK). Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? | -- | Go to Step 16 | --
16 |

1. Ensure that any components that you removed during diagnosis are installed in place.
2. Ensure that all connectors are connected.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

## Fuel Gage Inaccurate or Inoperative Pontiac

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. Turn the ignition switch to the RUN position.
2. Using a scan tool, inspect for Powertrain Control Module (PCM) diagnostic trouble codes (DTCs). Refer to Engine Controls in order to diagnose the PCM DTCs.
3. Turn the ignition switch to the OFF position.
4. Disconnect the fuel tank unit connector.
5. Connect the 2 red leads from the J 33431-C to the harness connector terminal B and terminal D.
6. Turn the ignition switch to the RUN position.
7. Set the tester resistance dials to 40 ohms (EMPTY).
8. Set the tester resistance dials to 248 ohms (FULL).

Does the fuel gauge display E at 40 ohms and F at 248 ohms?

--

Go to Step 4

Go to Step 3

3 |

1. Disconnect the instrument cluster connector.
2. Connect a J 39200 Digital Multimeter (DMM) between the instrument cluster connector terminal A14 and terminal A8 (UB3) or between connector C2 terminal A2 and terminal B8 (U50/U2F).
3. Set the tester resistance dials to 40 ohms.
4. Set the tester resistance dials to 248 ohms.

Does the J 39200 DMM voltage vary as the tester resistance changes?

--

Go to Step 6

Go to Step 5

4 |

1. Connect a scan tool.
2. Establish communications with the powertrain control module (PCM).
3. Set the tester resistance dials to 40 ohms (EMPTY).
4. Set the tester resistance dials to 248 ohms (FULL).

Does the PCM see a change in the fuel level sender data?

--

Go to Powertrain On Board Diagnostic (OBD) System Check Engine Controls

Go to Step 8

5 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the PCM connector C2.
3. Connect a J 39200 DMM between A14 and ground (UB3) or between connector C2 terminal A2 and ground (U50/U2F).

Does the J 39200 DMM display less than the specified value?

5 ohms

Go to Step 10

Go to Step 9

6 | Inspect the instrument cluster connector for proper terminal contact. Is the contact OK? | -- | Go to Step 7 | Go to Step 18
7 | Replace the instrument cluster.

• | For Buick only, refer to Instrument Cluster Replacement .

• | For Oldsmobile only, refer to Instrument Cluster Replacement .

• | For Pontiac only, refer to Instrument Cluster Replacement .

Is the replacement complete?

--

Go to Instrument Cluster System Check

--

8 | Inspect for a short to voltage or ground in CKT 1589. Was a problem found in CKT 1589? | -- | Go to Step 11 | Go to Step 12
9 | Connect a J 39200 DMM between the cluster connector terminal A14 (UB3) or connector C2 terminal A2 (U50/U2F) and the PCM connector C2 terminal 3. Does the J 39200 DMM display less than the specified value? | 5 ohms | Go to Powertrain On Board Diagnostic (OBD) System Check Engine Controls | Go to Step 13
10 | Inspect CKT 455 (PPL/WHT) for a short to ground. Was a problem found on CKT 455 (PPL/WHT)? | -- | Go to Step 14 | Go to Step 17
11 | Repair the short to voltage or ground in CKT 1589. Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? | -- | Go to Instrument Cluster System Check | --
12 | Inspect CKT 808 for an open. Is CKT 808 open? | -- | Go to Step 15 | Go to Step 16
13 | Repair the open in CKT 455 (PPL/WHT). Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? | -- | Go to Step 17 | --
14 | Repair CKT 455 (PPL/WHT) for a short to ground. Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? | -- | Go to Step 17 | --
15 | Repair the open in CKT 808. Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? | -- | Go to Step 17 | --
16 | Replace the fuel level sender. Refer to Fuel Sensor Assembly Replacement in Engine Controls. Is the replacement complete? | -- | Go to Step 17 | --
17 |

• | Ensure that any components that you removed during the diagnosis are installed in place.

• | Ensure that all connectors are connected.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

18 | Repair the terminal contact. Is the repair complete? | -- | Go to Instrument Cluster System Check | --