Buick Regal: DTC B2955 (with BTM)
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 B2955
Security Sensor Data Circuit
For symptom byte information, refer to Symptom Byte List.
Diagnostic Fault Information
Circuit/System Description
When a keyless entry transmitter is inserted into the transmitter pocket/slot
and the ignition mode switch
is pressed, the transponder embedded in the transmitter is energized by the
immobilizer antenna exciter
coil. The transponder transmits a signal to the body control module (BCM). The
BCM then compares this value to a value stored in memory. If the value is
correct, the BCM will send the prerelease
password via the serial data circuit to the engine control module (ECM). If the
learned key code does not
match or a transponder value is not received, the BCM will send the start
disable password to the ECM.
Conditions for Running the DTC
Ignition is in the Accessory or Run position.
Conditions for Setting the DTC
The BCM detects a circuit fault on the immobilizer antenna circuits.
Action Taken When the DTC Sets
- Vehicle starting will be disabled.
- The security indicator in the instrument cluster will be illuminated. A
service message will be
displayed in the driver information center.
Conditions for Clearing the DTC
- A current DTC will be cleared when the condition for setting the DTC are
no longer present.
- A history DTC will be cleared after 100 malfunction-free ignition
cycles.
Reference Information
Schematic Reference
Immobilizer Wiring Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEW INDEX
Master Electrical Component List
Description and Operation
Immobilizer 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. Verify DTC B2955 did not set immediately after the replacement or
programming of the K9 Body
Control Module or after performing the Immobilizer System Component Programming
procedure.
- If the DTC set immediately after the replace or programming of the K9
Body Control
Module or after performing the Immobilizer System Component Programming
procedure.
Perform the Immobilizer System Component Programming (without
BTM)Immobilizer System Component Programming (with BTM) procedure using a
new vehicle key. After the new key has been learned, the existing vehicle
keys may be
learned to the vehicle.
- Go to next step: If the DTC did not set immediately after the replace
or programming
of the K9 Body Control Module or after performing the Immobilizer System
Component Programming procedure.
2. Ignition OFF and all vehicle systems OFF, disconnect the harness connector
at the K89
Immobilizer Control Module. It may take up to 2 min for all vehicle systems to
power down.
3. Verify a test lamp illuminates between the low reference circuit terminal 1
and B+.
- If the test lamp does not illuminate
- Ignition OFF, disconnect the harness connector at the K9 Body Control
Module.
- Test for less than 2 Ω in the low 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 K9 Body Control Module.
- Go to next step: If the test lamp illuminates
4. Ignition ON.
NOTE: In some instances, the K9 Body Control Module may only apply
voltage for 3 s immediately after the ignition is turned ON. It may be
necessary to monitor the DMM while turning the ignition ON to
observe the voltage.
5. Test for greater than 9 V between the ignition circuit terminal 3 and
ground.
- Ignition OFF, disconnect the harness connector at the K9 Body Control
Module.
- Test for infinite resistance between the ignition 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 ignition circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K9 Body Control Module.
- Go to next step: If greater than 9 V
6. Ignition ON.
7. Test for 10 - 13 V between the serial data circuit terminal 2 and ground.
- Ignition OFF, disconnect the harness connector at the K9 Body Control
Module.
- Test for infinite resistance between the serial data 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 serial data circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K9 Body Control Module.
- Ignition OFF, disconnect the harness connector at the K9 Body Control
Module, 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.
- If less than 1 V, replace the K9 Body Control Module.
- Go to next step: If between 10 - 13 V
8. Replace the K89 Immobilizer Control Module.
9. Verify DTC B2955 does not set while operating the vehicle under the
conditions for running the
DTC.
Replace the K9 Body Control Module.
- Go to next step: If DTC B2955 is not set
10. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
Control Module References for body control module or immobilizer 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:
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
D
Front Wiper Blade
Replacement
Windshield wiper blades should be
inspected for wear or cracking.
It is a good idea to clean the wiper
blade assembly on a regular basis.
When worn, or when cleaning is
ineffective, replace the wiper blade.
Caution:
Allowing the wiper arm to touch
the windshield when