锟斤拷 If the OnStar GPS does not function, replace the K73 telematics communication interface module.
4. Ignition OFF, perform the coax cable test on the coax cable, refer to Component Testing. The coax cable should pass the test.
锟斤拷 If the coax cable does not pass the test, replace the coax cable.
5. If all circuits test normal, replace the T4 cellular phone and navigation antenna.
Caution: Refer to Test Probe Caution (See: Service Precautions/Vehicle Damage Warnings/Test Probe Caution).
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.
To prevent false reading when testing the center coax terminals, use care not to ground the test probe on the outer housing/shield.
Coax Cable Test
1. Ignition OFF, disconnect the GPS and cellular phone coax cable at both components.
2. Test both for less than 5 ohm between both ends of the coax cables center terminals.
锟斤拷 If greater than the specified range, replace the failed coax cable.
3. Test for greater than 10k ohm between the coax cable center wire and the outer coax shield.
锟斤拷 If less than the specified range, replace the coax cable.
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 telematics communication interface control
module replacement, setup, and programming
DTC B2462 (Navigation Radio)
* 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 B2462 02
- Global Positioning System (GPS) Short to Ground
DTC B2462 04
- Global Positioning System (GPS) Open Circuit
The global positioning system (GPS) antenna is connected to the navigation radio by a coaxial cable. The antenna cable also provides a path for DC
current for powering the antenna.
Conditions for Running the DTC
* Radio ON
* Battery voltage between 9-16 volts
* The navigation radio tests the GPS antenna every 10 seconds
Conditions for Setting the DTC