GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Lumina VE 🢒 DTC 🢒 DTC B2476

DTC B2476 RHD

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

DTC B2476 00: Cellular Phone Select Switch

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Keypad Supply Voltage

B2476 00

B2476 00

B2476 00

--

Circuit/System Description

The telematics button assembly on the inside rearview mirror assembly consists of 3 buttons, Information/End Call, Holden Assist and Emergency. Ten volts is supplied to the button assembly on the keypad supply voltage circuit. Each of the buttons, when pressed, completes the circuit across a resistor allowing a specific voltage to be returned to the telematics module on the keypad signal circuit. Depending upon the voltage range returned, the telematics module is able to identify which button has been pressed.

Conditions for Running the DTC
    • The radio is ON.
    • Battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

The communication interface module detects a short to voltage, short to ground, or an open/high resistance on the keypad supply voltage circuit.

Action Taken When the DTC Sets
    • No calls can be placed.
    • The communication interface module commands the red LED ON.
    • The communication interface module will ignore all inputs from the button assembly.

Conditions for Clearing the DTC
    • The condition for setting the DTC is no longer present.
    • The history DTC will clear after 100 fault-free ignition cycles.

Reference Information

Schematic Reference

Telematics Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Telematics 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

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the inside rearview mirror.
  2. Test for less than 5 Ω between the mirror ground circuit terminal 8 and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, test for less than 1 V between the keypad signal circuit terminal 11 and ground.
    4. ⇒If greater than the specified range, test the keypad signal circuit for a short to voltage. If the circuit tests normal, replace the communication interface module.
  4. Ignition OFF, test for 600 K - 700 K Ω between the keypad signal circuit terminal 11 and ground.
    5. ⇒If less than the specified range, test the keypad signal circuit for a short to ground. If the circuit tests normal, replace the communication interface module.
    ⇒If greater than the specified range, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the communication interface module.
  5. Ignition ON, test for 9.8-10.2 V between the keypad supply voltage circuit terminal 12 and ground.
    6. ⇒If less than the specified range, test the supply voltage circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the communication interface module.
    ⇒If greater than the specified range, test the supply voltage circuit for a short to voltage. If the circuit tests normal, replace the communication interface module.
  6. If all circuits test normal, test or replace the button assembly.

Component Testing
  1. Ignition OFF, disconnect the harness connector at the inside rearview mirror.
  2. Test for infinite resistance between the keypad supply voltage terminal 12 and the keypad signal terminal 11.
    3. ⇒If less than the specified range, replace the inside rearview mirror.
  3. Test for 1.4 K - 1.6 K Ω between the keypad supply voltage terminal 12 and the keypad signal terminal 11 while pressing the black phone button.
    4. ⇒If not within the specified range, replace the inside rearview mirror.
  4. Test for 2.7 K - 3.3 K Ω between the keypad supply voltage terminal 12 and the keypad signal terminal 11 while pressing the blue Holden Assist® button.
    5. ⇒If not within the specified range, replace the inside rearview mirror.
  5. Test for 2.7 K - 3.3 K Ω between the keypad supply voltage terminal 12 and the keypad signal terminal 11 while pressing the red emergency button.
    6. ⇒If not within the specified range, replace the inside rearview mirror.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Inside Rearview Mirror Replacement in Stationary Windows.
    •  Control Module References for communication interface module replacement, setup and programming.