For 1990-2009 cars

The OnStar Communication Interface Module (CIM) monitors the GPS coax for a short to ground in the GPS antenna coax circuit.

### DTC Parameters

• | The CIM must be On.

• | Short to ground on GPS coax.

• | Test runs once every second.

• | Illuminate the Red OnStar telltale.

Important: Do not perform an ohm's test on the circuit to the GPS antenna unless the coax is disconnected. Damage will results.

### 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.