Buick Regal: Unable to Contact OnStar Call Center
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.
- Refer to Diagnostic Procedure Instructions for 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
Circuit/System Description
The primary cellular phone antenna element is connected to the telematics
communication interface
control module (violet connector) via a shielded coaxial cable. Cellular
communication takes place on
both the primary cellular antenna signal circuit and the GPS/secondary cellular
antenna signal circuit.
This diagnostic only applies to the primary cellular antenna signal circuit.
Internal to the antenna on the
cellular antenna signal circuit resistance is used to apply a load, which the
telematics communication
interface control module uses to detect the presence of the antenna.
Conditions for Running the DTC
- Ignition in the RUN or ACC position.
- System voltage is between 9.5 V and 15.5 V.
- The above conditions are present for greater than 1 s.
Conditions for Setting the DTC
B2470 02
The telematics communication interface control module detects a short to
ground on the primary cellular
antenna signal circuit.
B2470 04
- The telematics communication interface control module detects an open or
high resistance on the
primary cellular antenna signal circuit.
- The above conditions are present for greater than 1 s.
Action Taken When the DTC Sets
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 Wiring Schematics
Connector End View Reference
Component Connector End View Index
Description and Operation
OnStar Description and Operation (UE1 with IOB/IO6) , OnStar Description
and Operation (UI3)
, or OnStar Description and Operation (UE1 without IOB/IO6).
Electrical Information Reference
- Refer to Circuit Testing
- Refer to Connector Repairs
- Refer to Testing for Intermittent Conditions and Poor Connections
- Refer to Wiring Repairs
Scan Tool Reference
Control Module References for scan tool information.
Special Tools
EL-49903-1 Test Antenna Navn-Cell Comn
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 min after turning the
ignition ON for the GPS satellites to acquire vehicle signal.
1. Ignition OFF/Vehicle OFF and all vehicle systems OFF, disconnect the
violet primary 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.
2. Using the EL-49903-1 Test Antenna Navn-Cell Comn connect the violet coax
cable to the K73
Telematics Communication Interface Control Module. Place the test antenna on the
roof of the
vehicle, ignition ON/vehicle in Service Mode.
3. Verify the DTC does not set or a call can be completed to the OnStar Call
Center while operating
the vehicle within the conditions for running the DTC.
- If the DTC sets or a call can not be completed to the OnStar Call
Center
Replace the K73 Telematics Communications Interface Control Module.
- Go to next step: If the DTC does not set or a call can be completed
to the OnStar Call
Center
4. Ignition OFF/Vehicle OFF.
5. Disconnect the EL-49903-1 Test Antenna Navn-Cell Comn from the K73 Telematics
Communication Interface Control Module
6. Test the coax cable. Refer to Component Testing.
- If the coax cable does not pass the test
Replace the coax cable.
- Go to next step: If the coax cable passes the test
7. Test or replace the T2RR Antenna - Roof Rear.
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
1. Test for less than 5 Ω between the coax cable center terminal end to end.
Replace the coax cable.
- Go to next step: If less than 5 Ω
2. Test for greater than 5 Ω between the coax cable outer shield end to end.
Replace the coax cable.
- Go to next step: If less than 5 Ω
3. 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.
- Go to next step: If infinite resistance
4. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair
procedure.
- Refer to High Frequency Antenna Replacement
- Refer to Control Module References for telematics communication
interface control module
replacement, setup, and programming
READ NEXT:
For issues with the Navigation system follow the steps below:
Verify the radio has the latest software installed
Verify the SD Card is fully installed and seated into the SD Card slot
Verify the S
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.
Refe
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.
Refe
SEE MORE:
Diagnostic Instructions
Perform the Diagnostic System Check prior to using this diagnostic
procedure: Refer to Diagnostic System
Check - Vehicle
Review the description of Strategy Based Diagnosis: Refer to Strategy
Based Diagnosis
An overview of each diagnostic category can be found here: R
Preliminary Procedure
Front Floor Console Replacement.
Theft Deterrent Module
Procedure
Disconnect the electrical connector.
Control Module References for programming and setup information, if
required.
IMMOBILIZER SYSTEM COMPONENT PROGRAMMING (WITHOUT BTM)
This procedure will learn t