DTC B13A7

Cellular, Entertainment, and Navigation | Diagnostic Information and Procedures | Document ID: 5184362 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. DTC Descriptors DTC B13A7 Coaxial Antenna RF signal 2 For symptom byte information refer to Symptom Byte List Diagnostic Fault Information

Circuit	Circuit Function	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performan
Antenna Coax Cable	FM 2	B13A7 11	B13A7 13	1	—
1. May exhibit possible FM interference.

Circuit/System Description The T35FB Radio Antenna Amplifier – FM2 is enabled when the A11 Radio is turned on. The A11  Radio provides battery voltage to the T35FB Radio Antenna Amplifier – FM2 using the center conductor of the antenna coaxial cable. When a 10 V signal is seen on the center conductor of the antenna coax, FM signals are amplified. Conditions for Running the DTC Ignition ON for more than 5 s. Battery voltage must be between 9–16 V. Conditions for Setting the DTC B13A7 11 The A11 Radio detects a short to ground in the antenna signal circuit center conductor. B13A7A 13 The A11 Radio detects an open in the antenna signal circuit center conductor. Action Taken When the DTC Sets A11 Radio reception may be poor or not available. Conditions for Clearing the DTC The condition responsible for setting the DTC no longer exists. A history DTC will clears after 100 consecutive malfunction-free ignition cycles have occurred. Reference Information Reference Information Schematic Reference Radio/Navigation System Schematics Connector End View Reference Master Electrical Component List Description and Operation Radio/Audio 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 Special Tools EL-52552 COAX FAKRA Cable Adaptor Kit Circuit/System Verification

1. Vehicle in service mode, A11 Radio on.
2. Verify station reception is normal when tuned to several known good FM stations. ⇒ If FM reception is poor. Refer to Circuit/System Testing ⇓ If reception is normal
3. All OK. Circuit/System Testing
4. Ignition OFF, disconnect the FM2 radio antenna coax cable from the A11 Radio and from the T35FB Radio Antenna Amplifier – FM2.
5. Verify the antenna coax cable passes the coax cable component test. Refer to Component Testing. ⇒ If the coax cable does not pass the test Replace the antenna coax cable ⇓ If the coax cable passes the test
6. Connect the radio antenna coax cable to the A11 Radio.
7. Connect the appropriate pinout adaptor from EL-52552 COAX FAKRA Cable Adaptor Kit to the coax cable at the T35FB Radio Antenna Amplifier – FM2.
8. Ignition ON, A11 Radio ON/vehicle in service mode, A11 Radio on.
9. Verify a test lamp illuminates between the terminals at the pinout adaptor.
10. Test for 9 V or greater between the terminals at the pinout adaptor. ⇒ If less than 9 V Replace the A11 Radio. ⇓ If 9 V or greater
11. Test or replace the T35FB Radio Antenna Amplifier – FM2. Component Testing

Note

Before testing the coax cable, check the cable exterior for being pinched, cut, damaged, or having loose connections at the components, which can cause reception issues. Coax Cable Test

1. Ignition OFF, disconnect the coax cable at both components.
2. Locate the appropriate pinout adaptor and load test loop adaptor from EL-52552 COAX FAKRA Cable Adaptor Kit.
3. Connect the 2 adaptors together, measure and record the resistance between the terminals at the pinout adaptor.
4. Disconnect the 2 adaptors and connect each one to the appropriate end of the coax cable.
5. At the pinout adapter, measure the total resistance of the coax cable loop including the connected load test adaptor. ⇒ If not within 5 Ω of the reading from step 3. Replace the coax cable ⇓ If within 5 Ω of the reading from step 3.
6. All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair. Radio Antenna Amplifier Replacement For control module replacement, programming, and setup refer to: Control Module References