DTC B2955
Diagnostic Instructions
DTC Descriptor
DTC B2955: Security Sensor Data Circuit
Malfunction
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
B+
|
B2955
|
B2955
|
--
|
--
|
Serial Data
|
B2955
|
B2955
|
B2955
|
B2955
|
Low Reference
|
--
|
B2955
|
--
|
--
|
Circuit/System Description
When an ignition key is inserted into the ignition lock cylinder
and the ignition is switched ON, the transponder embedded in the
key is energised by the exciter coils surrounding the ignition lock
cylinder. 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 is unable to measure the ignition key transponder
value.
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 centre. |
Conditions for Clearing the DTC
• |
A current DTC will be cleared when the BCM detects
a valid transponder value from the ignition key. |
• |
A history DTC will be cleared after
100 malfunction-free ignition cycles or when a scan tool is
used to clear DTCs. |
Reference Information
Schematic Reference
Immobiliser Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Immobiliser Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Inspect all available vehicle keys that they are
correct vehicle keys.
⇒ |
If not a correct vehicle key, replace the
key. |
- While viewing the scan tool BCM Transponder Key Part
Number, turn ON the ignition with each of the available vehicle
keys. The parameter should read a Key Part Number with all
available keys.
⇒ |
If only one key results in the parameter reading
no Part Number, replace the appropriate key. |
⇒ |
If no key results in the parameter reading no Part
Number, continue with test step 3. |
- Ignition OFF, disconnect the harness connector at the
K89 Immobilizer Control Module and disconnect the harness
connector X3 at the K9 Body Control Module. Test for
infinite resistance between the signal circuit listed below and
ground.
• |
K9 Body Control Module terminal 1 X3 |
• |
K9 Body Control Module terminal 2 X3 |
• |
K9 Body Control Module terminal 3 X3 |
⇒ |
If less than the specified range, test the
appropriate signal circuit for a short to ground. |
- Test for less than 0.3 V between the signal
circuit listed below and ground:
• |
K9 Body Control Module terminal 1 X3 |
• |
K9 Body Control Module terminal 2 X3 |
• |
K9 Body Control Module terminal 3 X3 |
⇒ |
If greater than the specified range, test the
appropriate signal circuit for a short to voltage. |
- Test for less than 5 Ω between the signal circuit
terminal listed below at the K9 Body Control Module and the
signal circuit terminal listed below at the K89 Immobilizer
Control Module.
• |
K9 Body Control Module
terminal 1 X3 and K89 Immobilizer Control Module
terminal 1 |
• |
K9 Body Control Module
terminal 2 X3 and K89 Immobilizer Control Module
terminal 2 |
• |
K9 Body Control Module
terminal 3 X3 and K89 Immobilizer Control Module
terminal 3 |
⇒ |
If greater than the specified range, test the
appropriate signal circuit for an open/high resistance. |
- If all circuits test normal, replace the
K89 Immobilizer Control Module and verify that the customer
concern is not still present.
⇒ |
If the customer concern is still present, replace
the K9 Body Control Module. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|