Circuit Description
The Passlock™ system is designed in order to prevent vehicle operation if the correct ignition key is not used in order to start the vehicle. The ignition key allows the lock cylinder to turn. Once the lock cylinder turns, the Passlock™ sensor (located inside the ignition switch assembly) sends an analog voltage code to the body control module (BCM). If the BCM receives the correct analog voltage code from the Passlock™ sensor, the BCM sends a class 2 serial data password to the vehicle control module (VCM). This action allows the vehicle to start.
Conditions for Setting the DTC
| • | The Passlock™ system uses 10 valid data values. The BCM only recognizes the last learned value as the correct value. |
| • | The BCM inspects the Passlock™ data for incorrect but valid data values during a start attempt. The BCM will continue to monitor the Passlock™ data during the engine running period. |
| • | The BCM inspects Passlock™ data for incorrect but valid data values for 1 second when the vehicle is not in the learn mode. |
Action Taken When the DTC Sets
| • | The vehicle will not start if the fault occurs before you start the vehicle. The security telltale will be FLASHING. |
| • | The vehicle will start if the fault occurs after the vehicle is running. The vehicle will be in the Fail Enable mode and the security telltale wil be ON. |
Conditions for Clearing the DTC
| • | All current DTCs (except B3031) clear once an ignition cycle occurs without the fault recurring. |
| • | A history DTC clears once 100 concurrent ignition cycles occur without the fault recurring. |
| • | Use a scan tool in order to clear history and current DTCs. |
Diagnostic Aids
| • | Use the scan tool in order to inspect the Passlock™ data voltage and the Passlock™ code. |
| • | When the ignition switch is turned from the OFF position to the RUN position, the security telltale will turn ON steady and then turn OFF after 3 seconds. |
| • | Perform a visual inspection of the wiring. |
| • | Perform a visual inspection of the connectors. |
| • | Inspect the Passlock™ sensor harness for an intermittent or poor connector, including the inline connector. |
| • | Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems for intermittent and poor connections. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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If the Passlock sensor has been replaced without the Theft Relearn Procedure, DTC B2960 will set.
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This step will determine if there is a leakage path in the Passlock sensor which would cause the Passlock code voltage to change.
Step | Action | Value(s) | Yes | No | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the VTD Diagnostic System Check? | -- | Go to Step 2 | |||||||||||||
Did you just replace the Passlock™ sensor? | -- | Go to Step 6 | Go to Step 3 | |||||||||||||
Does the scan tool indicate the specified value? Is the resistance within the specified range? | Less than 1000ohms | Go to Step 4 | Go to Step 5 | |||||||||||||
4 | Replace the BCM. Refer to Body Control Module Replacement in Body Control Systems. Is the repair complete? | -- | Go to Step 6 | -- | ||||||||||||
5 |
Is the repair complete? | -- | Go to Step 6 | -- | ||||||||||||
6 |
Is the operation complete? | -- | -- |
