Circuit Description
The Personal Automotive Security System (PASS-Key® II) is a vehicle theft deterrent system. The PASS-Key® II is designed in order to prevent vehicle theft by disabling the engine from starting unless an ignition key with a specific resistor pellet code is used in the ignition lock cylinder.
The ignition lock cylinder contains the resistor-sensing contacts. These contacts touch the resistor pellet that is embedded in the ignition key. When the ignition key is inserted in the ignition lock cylinder, the resistor pellet completes the key detection circuit (CKT 1073 and CKT 1074).
When the ignition switch is turned from the LOCK or the OFF position to the RUN position, the BCM applies a 5 V reference voltage to CKT 1073. The BCM reads the resistor pellet code and compares the stored resistor pellet code against the ignition key resistor pellet code for a correct match.
When the BCM detects a correct match, the BCM sends a fuel-enable password to the Powertrain Control Module (PCM) through the Class 2 serial data link. The PCM enables the theft deterrent relay. This action allows fuel delivery to the engine.
Conditions for Setting the DTC
| • | The resistance detected in CKT 1073 by the BCM is one of the 14 valid but incorrect PASS-Key® II resistance ranges. This condition signals an invalid resistor pellet code match. |
| • | The condition is present during an engine start attempt. |
| • | The condition is present for 1 second anytime after the engine has started. |
Action Taken When the DTC Sets
- If the PASS-Key® II resistance is out of range when attempting to start the vehicle, the BCM performs the following actions:
- If the PASS-Key® II resistance is initially correct (the engine starts), but later (during the same ignition cycle) the PASS-Key® II resistance is out of range, then the BCM performs the following actions:
| - | The BCM stores DTC B2960 in the memory. |
| - | The BCM sends a message to the Instrument Panel Cluster (IPC) to flash the SECURITY indicator through the Class 2 serial data link. |
| - | The BCM sends a message to the PCM via the Class 2 serial data link in order to perform the following actions: |
| • | Disable the theft deterrent relay |
| • | Stop the fuel delivery to the engine |
| - | The BCM disables sampling of the PASS-Key® II resistance or a waiting period of 3 minutes. |
| - | If the ignition switch is in the RUN position for at least 3 minutes, the BCM enters the theft deterrent re-learn mode. Refer to Body Control Module (BCM) Programming/RPO Configuration |
| - | The BCM stores DTC B2960 in the memory. |
| - | The BCM enters the fail-enable mode. |
| - | The BCM sends a message to the IPC in order to turn on the SECURITY indicator through the Class 2 serial data link. |
| - | Upon subsequent engine start attempts, the BCM sends a message to the PCM via the Class 2 serial data link in order to perform the following actions: |
| • | Enable the theft deterrent relay |
| • | Deliver fuel to the engine |
Conditions for Clearing the MIL/DTC
| • | The BCM detects a valid PASS-Key® II resistance value on the PASS-Key® II input circuit (CKT 1073). |
| • | A history DTC clears after 100 consecutive ignition cycles if the condition for the malfunction is no longer present. |
| • | Use a Scan Tool in order to clear the DTC. |
Diagnostic Aids
| • | The following conditions may cause an intermittent malfunction to appear: |
| - | Dirty or loose ignition cylinder key contacts |
| - | A dirty key resistor pellet |
| - | An incorrect PASS-Key® |
| - | An intermittent open or short to ground in CKT 1073 or CKT 1074 |
| - | Poor connections at the BCM or the ignition switch connector |
| • | If the key resistor pellet is incorrect, no communication will be possible from the BCM to the PCM in order to enable the theft deterrent relay or enable fuel delivery to the engine. This vehicle disable period state lasts approximately 3 minutes. During this waiting period, the SECURITY indicator flashes when the ignition switch is in the RUN position. Disconnecting the battery will not clear the timer sequence. The timer sequence will resume when the battery power is restored. Even if a proper key is inserted during the vehicle disable period, the vehicle will not start until the 3 minute waiting period has elapsed. After the 3 minute time period, the SECURITY indicator changes from a flashing state to a solid ON state. At this time, the BCM enters the theft deterrent re-learn mode. The engine will start if the correct ignition key resistor pellet is used. |
| • | Extremely hot or cold ambient conditions may possibly cause a DTC B2960. In order to eliminate this possibility, ensure that the vehicle and the key are near normal room temperature conditions during testing. Ensure that the key resistor contacts are clean and free of grease and oil. These substances may interfere with the key detection circuit and set this DTC. |
| • | Inspect for poor connections at the BCM and the ignition lock cylinder assembly. Poor connections at these components may cause an open, incorrect PASS-Key® II resistance or intermittent malfunction. If the DTC is a history DTC, the condition may be intermittent. Perform the tests shown while moving the wires and connectors. This action may often cause the malfunction to reappear. |
| • | DTC B2958 may set in the BCM when the ignition switch is in the RUN position with the steering column lock and the ignition key cylinder connector (C207) disconnected. When the BCM diagnostics and repairs are completed for DTC B2960, clear the DTCs and perform the BCM Diagnostic System Inspect. |
| • | The DTC P1626 sets in the Powertrain Control Module (PCM) when the ignition switch is in the RUN position and the BCM is disconnected. When BCM diagnostics and repairs are completed, refer to Engine Controls for additional information on PCM-related DTCs. |
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
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This step tests if the ignition keys supplied with the vehicle are within the allowable range.
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If certain BCM DTCs are present, perform the diagnostic tables for these DTCs first. The malfunction that caused these other DTCs to set may also set DTC B2960.
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This step determines if the ignition lock cylinder is functioning properly.
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This step tests for a faulty BCM.
-
This step determines if one of the ignition keys is faulty.
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Was the BCM Diagnostic System Inspect performed? | -- | Go to Step 2 | |||||||
|
Important: If a key does not start the vehicle, wait at least 3 minutes before inserting the next key. The PASS-Key® II system requires a 3 minute waiting period in order to reset the timer sequence. Attempt to start the engine using all of the ignition keys provided with the vehicle. Does the engine start using one of the ignition keys? | -- | Go to Step 6 | Go to Step 3 | |||||||
Inspect for BCM DTCs.
Are any of these current BCM DTCs present? | -- | Go to Step 4 | ||||||||
Perform the Lock Cylinder Test. Refer to Ignition Key Lock Cylinder Test in Theft Deterrent. Is the action complete? | -- | Go to Step 5 | -- | |||||||
Does DTC B2960 reset as a current DTC? | -- | Go to Step 8 | Go to Step 9 | |||||||
Do all of the ignition keys start the engine? | -- | Go to Step 5 | Go to Step 7 | |||||||
7 | Replace the malfunctioning ignition key(s). Refer to Programming Replacement Keys, Ignition Cylinder, or Powertrain Control Module in Theft Deterrent. Is the repair complete? | -- | Go to Step 10 | -- | ||||||
8 |
Is the repair complete? | -- | Go to Step 10 | -- | ||||||
9 | A malfunction is not present at this time. Refer to Diagnostic Aids for additional information. Is the action complete? | -- | Go to Step 10 | -- | ||||||
10 |
Are any current BCM DTCs set? | -- | System OK |
