For 1990-2009 cars

### Circuit Description

The VIU checks for a GPS signal every 2.5 seconds. If the VIU does not detect a GPS signal, DTC B2462 will set.

### Conditions for Running the DTC

• | The Ignition must be in the Run or ACC position.

• | The VIU will run this test every 2.5 sec.

• | Battery voltage must be at least 9.5 volts and no more than 15.5 volts.

### Conditions for Setting the DTC

The VIU does not receive a signal from the global position system (GPS) antenna.

### Action Taken When the DTC Sets

When DTC B2462 is current the VIU turns ON the RED OnStar® LED.

### Conditions for Clearing the DTC

• | The VIU detects the presence of a GPS antenna.

• | The VIU will automatically clear the code from history when the GPS antenna is present for 50 ignition cycles.

• | The VIU receives a clear code command from the scan tool.

### Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. This step tests for proper ground on the GPS antenna.

2. This step tests the condition of the GPS antenna.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: OnStar Schematics
1 | Did you perform the OnStar® Diagnostic System Check? | -- | Go to Step 2 | Go to Connector Repairs
2 | Important:: The GPS antenna and the coaxial cable grounding tab must be mounted to the metal roof with the maximum contact area. Test the GPS antenna coax cable ground for an open or high resistance. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs

Did you find and correct the condition?

--

Go to Step 3

Go to Connector Repairs

3 |

1. Inspect the GPS antenna connection at the VIU.
2. Inspect the antenna cable for pinches, scrapes and cuts.

Is the antenna cable OK?

--

Go to Step 6

Go to Step 4

4 | Inspect for poor connections at the harness connector of the antenna. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 8 | Go to Step 5
5 | Replace the GPS antenna. Refer to OnStar GPS Antenna Replacement . Is the repair complete? | -- | Go to Step 8 | --
6 | Inspect for poor connections at the harness connector of the VIU. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 8 | Go to Step 7
7 | Replace the VIU module. Refer to OnStar Vehicle Interface Unit Replacement . Did you complete the replacement? | -- | Go to Step 8 | --
8 |

1. Use the scan tool in order to clear the DTCs.
2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK