1. Ignition OFF, disconnect the cellular antenna coax from the CIM module and the cellular antenna.
2. Ignition ON, test for less than 1 volt between the antenna coax center terminal and ground.
锟斤拷 If greater than the specified range, replace the antenna coax.
3. Ignition ON, test for less than 1 volt between the antenna coax outer shield and ground.
锟斤拷 If greater than the specified range, replace the antenna coax.
4. Test for infinite resistance between the antenna coax center terminal and ground.
锟斤拷 If less than the specified value, replace the antenna coax
5. Test for infinite resistance between the antenna coax outer shield and ground.
锟斤拷 If less than the specified value, replace the antenna coax
6. Test for less than 5 ohms at the cellular antenna coax center terminal from end to end.
锟斤拷 If greater than specified value, replace the cellular antenna coax cable.
7. Test for less than 5 ohms at the cellular antenna coax outer shield from end to end.
锟斤拷 If greater than specified value, replace the cellular antenna coax cable.
8. Test for infinite resistance between the antenna coax center terminal and the outer shield.
锟斤拷 If less than specified value, replace the cellular antenna coax cable.
9. If coax cable tests normal, replace the cellular antenna.
10. Clear the DTCs and operate the vehicle within the conditions for running the DTC. Verify DTC B2470 does not set.
锟斤拷 If the DTC sets, replace the CIM.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Cellular Communications/Digital Radio Antenna Replacement (See: Accessories and Optional Equipment/Antenna/Antenna, Radio/Service
and Repair/Cellular Communications/Digital Radio Antenna Replacement)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for CIM replacement, setup, and programming
B2474
DTC B2474
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC B2474 07
- Navigation Display Head Backlighting Performance
Circuit Description
The internal backlighting of the navigation display screen located in the navigation radio.
Conditions for Running the DTC
* Radio ON.
* Battery voltage must be between 9-16 volts.
