Diagnostic Instructions
DTC Descriptors
DTC B125C 01: Satellite Antenna 1 Circuit Short to Battery
DTC B125C 02: Satellite Antenna 1 Circuit Short to Ground
DTC B125C 04: Satellite Antenna 1 Circuit Open Circuit
Circuit/System Description
The digital radio receiver (DRR), located inside the radio, receives digital radio information from the digital radio antenna located on the outside of the vehicle. The DRR is connected to the digital radio antenna via a shielded coax cable.
Conditions for Running the DTC
This DTC is run every 300 milliseconds.
Conditions for Setting the DTC
The radio detects a circuit fault in the digital radio antenna.
Action Taken When the DTC Sets
The radio displays No XM Signal or Check Antenna.
Conditions for Clearing the DTC
| • | A current DTC clears when the condition for setting the DTC is no longer present. |
| • | A history DTC clears after 100 malfunction-free ignition cycles. |
Reference Information
Schematic Reference
Radio/Navigation System Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Radio/Audio System Description and Operation
Electrical Information Reference
Special Tools
EL-48028 Digital Radio Test Antenna
Circuit System Verification
With the vehicle outside in an area with an unobstructed view of the southern sky, tune to XM. Verify XM reception is clear and the No XM Signal message is not displayed on the radio.
Circuit/System Testing
- Ignition OFF, disconnect the DRR antenna coax from the radio. Connect the
EL-48028 to the radio and place on the roof of the vehicle.
- Ignition ON, radio tuned to XM channel 1. Verify XM reception is improved.
| ⇒ | If the reception is not improved, replace the radio. |
- Ignition OFF, disconnect the antenna coaxial from the digital radio antenna.
- Ignition ON, test for 4.5-5.5 volts between the antenna coax center terminal and ground.
| ⇒ | If not within the specified range, replace the antenna coax. |
- Test for infinite resistance between the antenna coax center terminal and ground.
| ⇒ | If not the specified value, replace the antenna coax. |
- Test for less than 5 ohms end to end at the coax center conductor.
| ⇒ | If greater than the specified range, replace the antenna coax. |
- Test for less than 5 ohms end to end at the coax outer shield.
| ⇒ | If greater than the specified range, replace the antenna coax. |
- Test for infinite resistance between the antenna coax center conductor and the outer shield.
| ⇒ | If less than the specified range, replace the antenna coax. |
- If all circuits test normal, replace the digital radio antenna.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
