Circuit Description
Two antenna coax cables connect the digital radio antenna assembly to the digital radio receiver (DRR). The DRR supplies a regulated 5-volt signal, on the satellite coax cable, to power up the circuitry of the digital radio antenna. The satellite coax cable also carries the satellite antenna signal. The other coax cable carries the terrestrial antenna signal to the DRR.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B1259 Antenna Ground Circuit
DTC Symptom | DTC Symptom Descriptor |
|---|---|
04 | Open Circuit |
Conditions for Running the DTC
The following are conditions that must be present in order for the digital radio receiver to enable the diagnostics.
| • | The DRR is in the ACCESSORY or RUN power mode and Infotainment VN is allowed. |
| • | The system voltage is at least 9 volts and no more than 16 volts. |
| • | All the above conditions are present for greater than 50 ms. |
Conditions for Setting the DTC
The DRR detects an open in the antenna circuit.
Action Taken When the DTC Sets
| • | The radio displays "No XM Signal." |
| • | The radio produces no audio. |
Conditions for Clearing the DTC
| • | The conditions for setting the DTC are no longer present. |
| • | A history DTC clears after 100 malfunction free ignition cycles. |
| • | The DRR receives the clear code command from the scan tool. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Radio/Audio System Schematics Connector End Views Reference: Entertainment Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Does the scan tool indicate that DTC B1259 is current? | -- | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections |
3 | With a scan tool, observe the Digital Radio Antenna parameter in the digital radio receiver data list. Does the scan tool indicate that the Digital Radio Antenna parameter is within the specified range? | 1200-1800 mV | Go to Step 4 | Go to Step 5 |
Test the antenna cables for a short to ground. Refer to Circuit Testing in Wiring Systems. Did you find the condition? | -- | Go to Step 6 | Go to Step 10 | |
5 |
Does the voltage measure within the specified range? | 4.5-5.5 V | Go to Step 7 | Go to Step 8 |
6 | Replace the digital radio antenna cables. Refer to Digital Radio Antenna Cable Replacement . Did you complete the replacement? | -- | Go to Step 12 | -- |
7 | Test the antenna cables for an open or high resistance. Refer to Circuit Testing . Did you find the condition? | -- | Go to Step 6 | Go to Step 10 |
8 | Inspect for poor connections at the digital radio receiver (DRR). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9 |
9 | Replace the DRR. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 12 | -- |
10 | Inspect for poor connections at the digital radio antenna. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 11 |
11 | Replace the digital radio antenna. Refer to Cellular and Navigation Antenna Assembly Replacement . Did you complete the replacement? | -- | Go to Step 12 | -- |
12 |
Did you correct the condition? | -- | System OK | Go to Step 2 |
