For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### Circuit Description

The global positioning system (GPS) antenna is connected to the navigation radio by a shielded coaxial cable. The antenna cable also provides a path for DC current for powering the GPS antenna.

### Reference Information

#### Schematic Reference

Radio/Navigation System Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Navigation System Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Testing

Note: The global positioning system (GPS) requires a clear line of sight to the sky to operate properly. In most cases the GPS will not have reception near tall buildings or inside structures.

1. Ignition OFF, disconnect the GPS antenna coax cable from the navigation radio.
2. Ignition ON, test for 4.5-5.5 V between the coax cable center conductor terminal at the radio and ground.

⇒ | If not within the specified range, replace the radio.

3. If all circuits test normal, replace the GPS antenna.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Electronic Navigation Antenna Replacement

• | Control Module References for Radio replacement, setup, and programming