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 voltage detected in CKT 1073 by the BCM is high. This condition indicates that a short to B+ is present. |
| • | 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
| • | The BCM stores DTC B2957 in the memory. |
| • | The BCM sends a message to the IPC in order to turn on the SECURITY indicator through the Class 2 serial data link. |
| • | The BCM performs one of the two following actions: |
| - | If CKT 1073 or CKT 1074 is open or shorted to voltage when attempting to start the engine, the BCM will NOT send a message to the PCM to enable the theft deterrent relay or to deliver fuel to the engine. The engine will exhibit an engine no-crank condition. |
| - | If CKT 1073 or CKT 1074 is open is shorted to voltage after the engine has started, the BCM enters a fail-enable mode. Upon subsequent engine start attempts, the BCM sends a password message to the PCM via the Class 2 serial data link in order to enable theft deterrent relay and deliver fuel to the engine. The engine will start. |
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 open key resistor pellet |
| - | An incorrect PASS-Key® |
| - | An intermittent open or short to B+ in CKT 1073 or CKT 1074 |
| - | An open in the ignition cylinder key contacts |
| - | Poor connections at the BCM or the ignition lock cylinder |
| • | 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 an open or short to B+ in CKT 1073 or CKT 1074. |
| • | Inspect for poor connections at the BCM and the ignition lock cylinder assembly. Poor connections at these components may cause an open, short, 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 B2957 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 numbers below refer to the step numbers on the diagnostic table.
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This step inspects if the PASS-Key® II resistor pellet is within the allowable range.
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This step determines if the BCM output voltage to the ignition lock cylinder is within the proper range.
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This step tests for an open in CKT 1073.
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This step tests for a short to B+ in CKT 1073.
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This step tests for an open in CKT 1073.
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This step tests for a short to B+ in CKT 1074.
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This step tests for an open in CKT 1074.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
1 | Was the BCM Diagnostic System Inspect performed? | -- | Go to Step 2 | |
Inspect the vehicle's key code number by inserting the ignition key into the J 35628-A . Does the J 35628-A indicate a valid key code in the specified range? | 1-15 | Go to Step 3 | Go to Step 7 | |
Is the voltage within the specified range? | 4-6 V | Go to Step 6 | Go to Step 4 | |
|
Important: Do not use C207 terminal B for ground. Using the DMM, measure the voltage between C207 terminal A (BCM side) and ground. Is the voltage within the specified range? | 4-6 V | Go to Step 14 | Go to Step 10 | |
5 |
Does DTC B2958 reset as a current DTC? | -- | Go to Step 8 | Go to Step 18 |
6 | Replace the ignition lock cylinder. Refer to Steering Column Lock Cylinder Set - Disassemble - Off Vehicle in Steering. Is the repair complete? | -- | Go to Step 5 | -- |
7 | Replace the ignition key. Refer to Theft Deterrent. Did you replace the key? | -- | Go to Step 9 | -- |
8 |
Is the repair complete? | -- | Go to Step 9 | -- |
9 |
Are any current BCM DTCs set? | -- | System OK | |
Do not disconnect the DMM. Disconnect the BCM connector C1. Using the DMM, measure the voltage between C207 terminal A (BCM side) and ground. Is the voltage less than the specified value? | 2 V | Go to Step 12 | Go to Step 11 | |
11 | Repair the short to B+ in CKT 1073. Is the repair complete? | -- | Go to Step 9 | -- |
Using the J 39200 DMM, measure the resistance between BCM harness connector C2 terminal B3 and C207 terminal A (BCM side). Is the resistance less than the specified value? | 2 ohms | Go to Step 5 | Go to Step 13 | |
13 | Repair the poor connection or the open in CKT 1073. Is the repair complete? | -- | Go to Step 9 | -- |
Using the DMM, measure the voltage between C207 terminal B (BCM side) and ground. Is the voltage less than the specified value? | 2 V | Go to Step 16 | Go to Step 15 | |
15 | Repair the short to B+ in CKT 1074. Is the repair complete? | -- | Go to Step 9 | -- |
Using the DMM, measure the resistance between BCM harness connector C2 terminal B4 and C207 terminal B (BCM side). Is the voltage less than the specified value? | 2 ohms | Go to Step 5 | Go to Step 17 | |
17 | Repair the poor connection or the open in CKT 1074. Is the repair complete? | -- | Go to Step 9 | -- |
18 | A malfunction is not present at this time. Refer to Diagnostic Aids for additional information. Is the action complete? | -- | System OK | -- |
