Buick Regal: DTC B2476 or B2482
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 B2476 04
Cellular Phone Select Service Switch Open
DTC B2476 59
Cellular Phone Select Service Switch Protection Time-out
DTC B2482 00
Cellular Phone Select Service Switch Range/Performance
Diagnostic Fault Information
Circuit/System Description
The OnStar button assembly consists of 3 buttons: Call/Answer, OnStarÂ
Call Center, and
OnStar Emergency. The telematics communication interface control module
supplies the OnStarÂ
button assembly with 10 V via the 10 V reference circuit. Each of the buttons,
when pressed, completes
the circuit across a resistor allowing a specific voltage to be returned to the
telematics communication interface control module over the keypad signal
circuit. Depending upon the voltage range returned, the
telematics communication interface control module is able to identify which
button has been pressed.
Conditions for Running the DTC
- Vehicle in Service Mode/Ignition ON.
- Battery voltage must be between 9 - 16 V.
Conditions for Setting the DTC
B2476 04
The telematics communication interface control module detects an open/high
resistance on the keypad
supply voltage circuit.
B2482 and B2476 59
The telematics communication interface control module detects a valid signal
on the keypad signal
circuit for longer than 15 s. If one of the OnStar buttons is held or stuck
for 15 s or greater, the
telematics communication interface control module will set this DTC.
Action Taken When the DTC Sets
- The OnStar status LED turns red.
- No calls can be placed.
- The telematics communication interface control module will ignore all
inputs from the OnStarÂ
button assembly.
Conditions for Clearing the DTC
- The condition responsible for setting the DTC no longer exists.
- A history DTC will clear once 50 consecutive malfunction-free ignition
cycles have occurred.
Diagnostic Aids
After any repair is made to the 10 V reference circuit or button signal
circuit the fuse to the telematics
communication interface control module must be removed for 30 s to reset the
control module. Failure
to do so could result in incorrect diagnosis.
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.
Circuit/System Testing
NOTE:
- 10 V reference circuit measurement may vary with vehicle battery
voltage.
- Test for voltage range with vehicle battery measuring at a minimum
of 11.5 V
1. Vehicle OFF/Ignition OFF and all vehicle systems OFF, disconnect the
harness connector at the
A98 Front Overhead Console Assembly. It may take up to 2 min for all vehicle
systems to power
down.
2. Test for less than 10 Ω between the ground circuit terminal 5 and ground.
- Vehicle OFF/Ignition OFF.
- Test for less than 2 Ω in the ground circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, repair the open/high resistance in the ground
connection.
- Go to next step: If less than 10 Ω
3. Vehicle in Service Mode/Ignition ON.
4. Test for 8.0 - 10.5 V between the 10 V reference circuit terminal 16 and
ground.
- Vehicle OFF/Ignition OFF, disconnect the harness connector at the K73
Telematics
Communication Interface Control Module.
- Test for infinite resistance between the 10 V reference circuit and
ground.
- If less than infinite resistance, repair the short to ground on the
circuit.
- Go to next step: If infinite resistance
- Test for less than 2 Ω in the 10 V reference circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K73 Telematics Communication Interface
Control
Module.
- Vehicle OFF/Ignition OFF, disconnect the harness connector at the K73
Telematics
Communication Interface Control Module, vehicle in Service Mode/Ignition ON.
- Test for less than 1 V between the 10 V reference circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K73 Telematics Communication Interface
Control
Module.
- Go to next step: If between 8.0 - 10.5 V
5. Vehicle OFF/Ignition OFF.
6. Test for 500 - 900 Ω between the signal circuit terminal 17 and ground.
- Disconnect the X1 harness connector at the K73 Telematics Communication
Interface
Control Module.
- Test for infinite resistance between the signal circuit and ground.
- If less than infinite resistance, repair the short to ground on the
circuit.
- If infinite resistance, replace the K73 Telematics Communication
Interface Control
Module.
- Disconnect the X1 harness connector at the K73 Telematics Communication
Interface
Control Module, vehicle in Service Mode/Ignition ON.
- Test for less than 1 V between the signal circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- Go to next step: If less than 1 V
- Vehicle OFF.
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K73 Telematics Communication Interface
Control
Module.
- Go to next step: If between 500 - 900 Ω
7. Test or replace the A98 Front Overhead Console Assembly.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
- Refer to Roof Console Replacement
- Refer to 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.
Refe
Note: The Following Steps Must Be Completed Before Using The Symptom
Table.
1. Perform The Diagnostic System Check - Vehicle Before Using The Symptom
Tables In Order To
Verify That All Of The Follow
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 - 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 Descriptor
DT
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 Descriptor
DT