B1272

DTC B1272

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.



DTC Descriptors
DTC B1272 02
- Antenna FM/AM Signal Circuit Low Voltage

DTC B1272 04
- Antenna FM/AM Signal Circuit Open




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



Conditions for Running the DTC

Radio ON


Conditions for Setting the DTC

A short to ground or an open/high resistance is detected on the radio antenna coax.


Action Taken When the DTC Sets

No action is taken when this DTC sets.


Conditions for Clearing the DTC

* A current DTC will clear when the conditions for setting the DTC are no longer present.
* A history DTC will clear after 100 malfunction free ignition cycles.



Reference Information
Schematic Reference

Radio/Audio System Schematics (Radio/Audio System Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Radio/Audio System Description and Operation (Radio/Audio System Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information


Circuit/System Testing

1. Disconnect the harness connector at the radio antenna.
2. Ignition OFF, test for less than 10 ohms between the terminal 2 outer shield and ground.

• If greater than the specified range, test the antenna coax shield for an open/high resistance. If the coax test normal, replace the radio.

3. Ignition ON, test the terminal 2 center terminal for 9.5-11.0 volts.

• If greater than the specified range, test the antenna coax center terminal for a short to voltage. If the coax tests normal, replace the radio.
• If less than the specified range, test the antenna coax center terminal for a short to ground or an open/high resistance. If the coax tests normal, replace the radio.

4. 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 (L48) (Radio Antenna Replacement (L48))Radio Antenna Replacement (L08) (Radio Antenna Replacement (L08))
* Antenna Cable Replacement (Coupe) (Antenna Cable Replacement (Coupe))Antenna Cable Replacement (Sedan) (Antenna Cable Replacement (Sedan))