Buick Regal: OnStar Button Led Malfunction
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
1. OnStar LED Inoperative
2. LED Illuminated At All Times
Circuit Description
The OnStar status LEDs are located in the inside rearview mirror telematic
button assembly. The
green LED is illuminated when the system is ON and operating normally. When the
green LED is green
and flashing, it is an indication that a call is in progress. When the red LED
is illuminated, a system
malfunction is present. In the event there is a system malfunction and the
OnStar system is still able
to make a call, the LED will flash red during the call. The OnStar LEDs are
controlled by the
telematics communication interface control module via the keypad green LED
control circuit and the
keypad red LED control circuit.
Conditions for Running the DTC
- Ignition ON.
- Battery voltage must be between 9 - 16 V.
Conditions for Setting the DTC
B2476 04
The telematics communication interface control module detects a short to
voltage or an open/high
resistance on the keypad 10 V reference 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.
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 Verification
NOTE: If the green LED is off with the ignition ON and the LED does not
function
when commanded with the scan tool, contact the OnStar Center to
confirm the vehicle has a current subscription. Without a current
subscription the LED's will not illuminate even when commanded with
the scan tool.
1. Ignition ON.
2. Verify no DTC are set.
Refer to Diagnostic Trouble Code (DTC) List - Vehicle
- Go to next step: If no DTC are set
3. Verify that the green LED turns ON and OFF when commanding the Green
Indicator ON and OFF
with a scan tool.
- If the green LED does not turn ON and OFF
Refer to Circuit/System Testing - Green LED Test
- Go to next step: If the green LED turns ON and OFF
4. Verify that the red LED turns ON and OFF when commanding the Red Indicator
ON and OFF
with a scan tool.
- If the red LED does not turn ON and OFF
Refer to Circuit/System Testing - Red LED Test
- Go to next step: If the red LED turns ON and OFF
5. All OK.
Circuit/System Testing
Green LED Test
1. Ignition OFF, and all vehicle systems OFF, disconnect the harness
connector at the A10 Inside
Rearview Mirror. It may take up to 2 min for all vehicle systems to power down.
Doors closed,
courtesy lamps OFF.
2. Test for less than 10 Ω between the ground circuit terminal 5 and ground.
- 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. Ignition ON.
4. Test for less than 1 V between the control circuit terminal 6 and ground
while commanding the
Green Indicator OFF with a scan tool.
- Ignition OFF, disconnect the X1 harness connector at the K73 Telematics
Communication
Interface Control Module, ignition ON.
- Test for less than 1 V between the control circuit terminal 6 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 less than 1 V
5. Test for greater than 8 V between the control circuit terminal 6 and
ground while commanding the
Green Indicator ON with a scan tool.
- Ignition OFF, disconnect the X1 harness connector at the K73 Telematics
Communication
Interface Control Module.
- Test for infinite resistance between the control circuit terminal 6 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 control 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 greater than 8 V
6. Test or replace the A10 Inside Rearview Mirror.
Red LED Test
1. Ignition OFF, and all vehicle systems OFF, disconnect the harness
connector at the A10 Inside
Rearview Mirror. It may take up to 2 min for all vehicle systems to power down.
Doors closed,
courtesy lamps OFF.
2. Test for less than 10 Ω between the ground circuit terminal 5 and ground.
- 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. Ignition ON.
4. Test for less than 1 V between the control circuit terminal 7 and ground
while commanding the
Red Indicator OFF with a scan tool.
- Ignition OFF, disconnect the X1 harness connector at the K73 Telematics
Communication
Interface Control Module, ignition ON.
- Test for less than 1 V between the control circuit terminal 7 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 less than 1 V
5. Test for greater than 8 V between the control circuit terminal 7 and
ground while commanding the
Red Indicator ON with a scan tool.
- Ignition OFF, disconnect the X1 harness connector at the K73 Telematics
Communication
Interface Control Module.
- Test for infinite resistance between the control circuit terminal 7 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 control 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 greater than 8 V
6. Test or replace the A10 Inside Rearview Mirror.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
- Refer to Inside Rearview Mirror 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
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:
If equipped with base seats, the
vehicle's front seats have adjustable
head restraints in the outboard
seating positions.
If equipped with GS Model seats,
the vehicle's front seats have head
restraints in the outboard seating
positions that cannot be adjusted.
Warning:
With head restraints that are
1. Perform the Diagnostic System Check - Vehicle, before using the Symptom
Tables in order to verify that all
of the following are true:
The control modules can communicate via the serial data link.
If one of the current or previous sensor learn is not successful.
If there are dashes displayed