Radio Poor Reception
Radio Poor Reception
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
AM and FM radio reception is dependent on the following components:
* Radio antenna
* Coax cable between the radio antenna and the radio
* Radio
The AM/FM radio antenna is located on the roof of the vehicle. The radio antenna is enabled when the radio is turned on. The radio supplies battery voltage to the antenna via the coax cable. An internal amplifier amplifies the radio signals from the antenna and transmits them to the radio.
Diagnostic Aids
Poor AM and FM radio reception is dependent on multiple influences, some of which may not be vehicle related. Areas which have high RF traffic or block the signal path may cause a degradation in radio reception. Radio reception may also be influenced by items within the vehicle, but not part of the radio system. Such examples are aftermarket electrical accessories or other items which may generated noise in the vehicle electrical system.
AM reception is highly dependent on the antenna receiving battery voltage from the radio. The antenna has a built in antenna amplifier that boosts both AM and FM reception. If the antenna does not receive battery voltage, the radio will still receive FM stations but AM stations will not be received.
Reference Information
Schematic Reference
Radio/Navigation System Schematics Radio/Navigation System Schematics
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
Description and Operation
Radio/Audio System Description and Operation Radio/Audio System
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Inspect the antenna for proper mounting or physical damage.
• If damage is found, repair or replace as necessary
2. Verify no DTCs are set as current.
• If any DTCs are set as current, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
Circuit/System Testing
Note:
Before testing, inspect the antenna coax cable for damage or poor connections.
1. Ignition OFF, disconnect the radio antenna coax cable from the radio.
2. Ignition ON, test for B+ between the coax cable connection center conductor at the radio and ground.
• If not the specified value, replace the radio.
3. Ignition OFF, reconnect the antenna coax cable at the radio. Disconnect the antenna coax cable from the radio antenna.
• If less than the specified value, replace the antenna coax.
4. Ignition ON, test for B+ between the coax cable connection center conductor and the coax cable outer shield.
• If not the specified value, replace the antenna coax cable.
5. If all circuits test normal, replace the radio antenna.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Radio Antenna Replacement Service and Repair
* Control Module References Control Module References for radio replacement, setup, and programming