For 1990-2009 cars

The OnStar Communication Interface Module (CIM) monitors the GPS coax for an open in the GPS antenna coax circuit.

### DTC Parameters

• | CIM power On.

• | Open in GPS coax.

• | Test runs once every second.

• | Illuminate the Red OnStar telltale.

Important: Do not perform an ohms test on circuits to the GPS antenna unless the coax is disconnected or damage will result.

### Diagnostic Aids

If the condition is suspected to be intermittent, moving the wires may help in duplicating the condition. Check the connections at the antenna and the inline connector.