Chevrolet Trax: DTC B2470: Cellular phone antenna
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 B2470 02
Cellular Phone Antenna Circuit Malfunction Short to Ground
DTC B2470 04
Cellular Phone Antenna Circuit Malfunction Open Circuit
Diagnostic Fault Information
Circuit/System Description
The cellular phone and navigation antenna is connected to the telematics
communication interface control
module. This module supplies 5 V to the cellular phone and navigation antenna to
power the internal amplifier.
When the vehicle is equipped with the optional navigation radio, a navigation
antenna signal splitter is installed
to distribute the GPS signal to both the telematics communication interface
control module and the navigation
radio. The navigation radio supplies 5 V through the GPS antenna coaxial cable
to the navigation antenna signal
splitter to power the internal navigation radio signal amplifier.
Conditions for Running the DTC
- Ignition in the RUN or ACC position.
- System voltage is between 9.5 volts and 15.5 volts.
- The above conditions are present for greater than 1 s.
Conditions for Setting the DTC
- The telematics communication interface control module does not detect
the presence of a cellular
antenna.
- The above conditions are present for greater than 1 s.
Action Taken When the DTC Sets
- The vehicle is unable to connect to the OnStar Call Center.
- The OnStar status LED turns red.
Conditions for Clearing the DTC
- The telematics communication interface control module detects the
presence of a cellular antenna.
- A history DTC clears after 50 malfunction-free ignition cycles.
Reference Information
Schematic Reference
OnStar/Telematics Schematics (Encore), OnStar/Telematics Schematics (Trax)
Connector End View Reference
WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS -
INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT
CONNECTOR END VIEWS - INDEX - TRAX
Description and Operation
OnStar 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-49903 GM OnStar Antenna Diagnostic Tool Kit
Circuit/System Testing
NOTE:
- The vehicle may be equipped with sectioned coax. Test each section
and
replace only the faulty section, not the entire length of coax.
- The following verification requires the vehicle to be outside with an
unobstructed view of the southern sky. Allow 5 minutes after turning the
ignition ON for the GPS satellites to acquire vehicle signal.
Without Navigation Radio
- Ignition OFF and all vehicle systems OFF, disconnect the GPS and
cellular coax cable connector at the
K73 Telematics Communication Interface Control Module. It may take up to 2
min for all vehicle
systems to power down.
- Using the EL-49903-3 kit (EL-49903-5 adapter and EL-49903-4 coax cable),
connect the EL-49903 GM
OnStar antenna diagnostic tool kit to the K73 Telematics Communication
Interface Control Module.
Place the test antenna on the roof of the vehicle, ignition ON.
- Verify the DTC does not set while operating the vehicle within the
conditions for running the DTC.
Replace the K73 Telematics Communications Interface Control Module.
- Ignition OFF.
- Disconnect the EL-49903 GM OnStar antenna diagnostic tool kit from the
K73 Telematics
Communication Interface Control Module
- Test the coax cable. Refer to Component Testing.
If the coax cable does not pass the test
Replace the coax cable.
If the coax cable passes the test
- Test or replace the T4G Cellular Phone, Navigation, and Digital Radio
Antenna.
With Navigation Radio
- Ignition OFF and all vehicle systems OFF, disconnect the GPS and
cellular coax cable connector at the
K73 Telematics Communication Interface Control Module. It may take up to 2
min for all vehicle
systems to power down.
- Using the EL-49903-3 kit (EL-49903-5 adapter and EL-49903-4 coax cable),
connect the EL-49903 GM
OnStar antenna diagnostic tool kit to the K73 Telematics Communication
Interface Control Module.
Place the test antenna on the roof of the vehicle, ignition ON.
- Verify the DTC does not set while operating the vehicle within the
conditions for running the DTC
If the DTC sets
Replace the K73 Telematics Communication Interface Control Module.
If the DTC does not set
- Ignition OFF.
- Disconnect the EL-49903 GM OnStar antenna diagnostic tool kit from the
K73 Telematics
Communication Interface Control Module
- Connect the coax cable to the K73 Telematics Communications Interface
Control Module and disconnect
the coax cable from the T15 Navigation Antenna Signal Splitter, ignition ON.
- Test for 4.5-5.5 V between the coax cable center conductor and the outer
shield.
If less than 4.5 V
- Ignition OFF.
- Test the coax cable. Refer to Component Testing.
- If the coax cable does not pass the test, replace the coax cable.
- If the coax cable passes the test, test or replace the K73 Telematics
Communications
Interface Control Module.
If greater than 5.5 V
- Ignition OFF.
- Test the coax cable. Refer to Component Testing.
- If the coax cable does not pass the test, replace the coax cable.
- If the coax cable passes the test, test or replace the K73 Telematics
Communications
Interface Control Module.
If between 4.5-5.5 V
- Ignition OFF, connect the coax cable to the T15 Navigation Antenna
Signal Splitter and disconnect the
coax cable from the T4G Cellular Phone, Navigation, and Digital Radio
Antenna, ignition ON.
- Test for 4.5-5.5 V between the coax cable center conductor and the outer
shield.
If less than 4.5 V
- Ignition OFF.
- Test the coax cable. Refer to Component Testing.
- If the coax cable does not pass the test, replace the coax cable.
- If the coax cable passes the test, test or replace the T15 Navigation
Antenna Signal Splitter.
If greater than 5.5 V
- Ignition OFF.
- Test the coax cable. Refer to Component Testing.
- If the coax cable does not pass the test, replace the coax cable.
- If the coax cable passes the test, test or replace the T15 Navigation
Antenna Signal Splitter.
If between 4.5-5.5 V
- Test or replace the T4G Cellular Phone, Navigation, and Digital Radio
Antenna.
Component Testing
CAUTION: Refer to 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 readings when testing the center coax terminals, use
care
not to ground the test probe on the outer housing/shield.
Coax Cable Test
- Ignition OFF, disconnect the coax cable at both components.
- Test for less than 5 ohms between the coax cable center terminal end to
end.
If 5 ohms or greater
Replace the coax cable
If less than 5 ohms
- Test for greater than 5 ohms between the coax cable outer shield end to
end.
If 5 ohms or greater
Replace the coax cable.
If less than 5 ohms
- Test for infinite resistance between the coax cable center terminal and
the coax cable outer shield.
If less than infinite resistance
Replace the coax cable.
If infinite resistance
- All OK.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
- Radio Antenna Base Replacement
- Control Module References for Telematics Communication Interface Control
Module replacement,
programming and setup.
READ NEXT:
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.
Diag
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.
Diag
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.
Diag
SEE MORE:
Removal Procedure
Place drain pans under the vehicle.
Remove as much power steering fluid from the power steering fluid
reservoir as possible.
Fig. 24: Steering Fluid Reservoir Outlet Hose And Clamp
Release the power steering fluid reservoir outlet hose clamp (1) and
disconnect the power
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 provide an overview of each diagnostic
category.
Diagnostic Fault I