For 1990-2009 cars
Body Control Module Components
Cell 51: Fuel Tank Module, Instrument Cluster and Passlock Cylinder

### Circuit Description

This is the fault code (current and history) that is set when the body control module (BCM) detects a short to ground at the BCM fuel sensor input.

### Conditions for Setting the DTC

Meet all of the following conditions:

• | Ignition 0 is active.

• | The voltage ratio of the fuel level voltage to the battery voltage is less than 1% for 2.55 seconds.

### Action Taken When the DTC Sets

• | Fuel gauge displays empty

• | Low fuel indicator illuminates

• | Stores DTC P0462 in the BCM memory

### Conditions for Clearing the DTC

• | The BCM goes to sleep and reinitializes with the fault cleared.

• | All the BCM history codes will be cleared after 100 ignition cycles (from OFF to RUN) with no current codes active during the 100 ignition cycles.

• | Use the Scan Tool .

### Diagnostic Aids

• | When the diagnostics direct you to take electrical measurements at the junction blocks, refer to Power Distribution Schematics in Wiring Systems for terminal assignments of the junction blocks.

• | If the DTC is a history DTC, the problem may be intermittent. Perform the above tests while wiggling the wiring and connectors. This may often cause the malfunction to appear.

### Test Description

The numbers below refer to the numbers on the diagnostics table.

1. This step determines if the body control module (BCM) is reading the fuel level sensor.

2. This step determines if there is a short to ground in CKT 470 between the fuel level sensor and the BCM.

3. This step determines if there is a short to ground in CKT 470 within the left IP junction block.

4. This step determines if there is an open in CKT 470 between the left IP junction block and the BCM.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the BCM System Check performed? | -- | Go to Step 2 | Go to Body Control Module System Check
2 |

1. Disconnect the fuel tank module connector.
2. Use a Scan Tool in order to measure the fuel tank module resistance CKT 470.

Is the measured fuel tank module resistance greater than the specified value?

250 ohms

Go to Step 9

Go to Step 3

3 |

1. Back out the left IP junction block connector C3 terminal A12 CKT 470.
2. Use a Scan Tool in order to measure the fuel tank module resistance CKT 470.

Is the measured fuel tank module resistance greater than the specified value?

250 ohms

Go to Step 5

Go to Step 4

4 | Repair the short to ground in CKT 470 between the fuel tank module connector terminal D and the left IP junction block connector C3 terminal A12. Is the repair complete? | -- | Go to Step 12 | --
5 |

1. Back out the left IP junction block connector C2 terminal A1 CKT 470.
2. Use a Scan Tool in order to measure the fuel tank module resistance CKT 470.

Is the measured fuel tank module resistance greater than the specified value?

250 ohms

Go to Step 8

Go to Step 6

6 | Use the J 39200 in order to measure the resistance in CKT 470 between the left IP junction block harness connector C2 terminal A1 and ground. Does the measured fuel tank module resistance equal the specified value? | Infinite | Go to Step 9 | Go to Step 7
7 | Repair the short to ground in CKT 470 between the left IP junction block connector C2 terminal A1 and the BCM connector C2 terminal A4. Is the repair complete? | -- | Go to Step 12 | --
8 | Replace the left IP junction block. Is the repair complete? | -- | Go to Step 12 | --
9 |

1. Reconnect all the components.
2. Replace the fuel tank module. Refer to Fuel Tank Replacement in Engine Controls - 2.4L or Fuel Tank Replacement in Engine Controls - 3.1L.

Is the repair complete?

--

Go to Step 10

--

10 | Clear the DTCs from the memory. Does DTC P0462 remain current? | -- | Go to Step 11 | Go to Step 12
11 | Replace the BCM. Refer to the following procedures:

• | Body Control Module (BCM) Programming/RPO Configuration

• | Body Control Module Replacement

Is the repair complete?

--

Go to Step 12

--

12 | Clear the DTCs from the memory. Are the DTCs cleared from the memory? | -- | Go to Body Control Module System Check | --