My neighbor changed the steering wheel on a 2001 suburban and now security light is on. Now the truck starts then dies. I need a passlock diagram

Is there a security lamp on the dash that is on or flashing? Any applicable trouble codes? My info shows you have passlock, usually a fuel injector disable, only, may start and stall. If vehicle starts and stalls, leave key in the on position, If security lamp does not flash, the passlock system should not be at fault.

Passlock on this vehicle shows the key does not have a pellet and no transponder. It's just a mechanical key. It is the tumbler that communicates with passlock sensor. The passlock sensor wiring is noted for problems. Can you check applicable trouble codes?

Passlock sensor Problem 2001 Chevy Suburban/Truck ...

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www.youtube.com/watch?v=EVjU0fh5h5s
Jan 29, 2013 - Uploaded by nightbandit007 Passlock sensor issues with 2001 Chevy Suburban. This is not how to bypass the system completely or .

Do you have a security light lit or flashing on the Instrument cluster ?
The theft deterrent system has been incorporated into the body control module (BCM). The theft deterrent is provided in order to prevent the vehicle operation if the correct key is not used in order to start the vehicle. The ignition key turns the lock cylinder. The cylinder rotation produces an analog voltage code in the passlock?"¢ sensor. This voltage code is received by the BCM. The BCM compares the voltage code to the previousely learned voltage code. If the codes match, a class 2 message is sent from the BCM to the powertrain control module (PCM)/vehicle control module (VCM). The message enables the fuel injectors.
The design of the passlock?"¢ system is to prevent vehicle theft by disabling the engine unless the ignition lock cylinder rotates properly by engaging the correct ignition key. The system is similar in concept to the passkey system. However, the passlock?"¢ system eliminates the need for a key mounted resistor pellet. The components of the passlock?"¢ system are as follows:
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The ignition lock cylinder

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The ignition switch

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The passlock?"¢ sensor

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The Body control module (BCM)

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The security telltale

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The vehicle/powertrain control module (VCM/PCM)

The ignition lock cylinder is located at the upper right side of the steering column. The Passlock?"¢ sensor is in the steering column. The Passlock?"¢ sensor is separate from the key and lock cylinder. The key and the lock cylinder work together in order to determine if the proper ignition key was used to start the vehicle.
In the event of an open Class 2 serial data line between the BCM and the VCM/PCM, the vehicle will become fail-enabled if the VCM/PCM has already received the password from the BCM for that ignition cycle (the engine is running). In this event, the following conditions occur:
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The security telltale will be ON continuously.

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The VCM/PCM will become fail-enabled for future ignition cycles.

If a failure in the Class 2 serial data line occurs before the ignition cycle, when the VCM/PCM is not fail-enabled, the following conditions occur:
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The VCM/PCM will never receive a valid password in order to enable the fuel injectors.

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The vehicle will not start.

The lock cylinder and the visible key insert portion of the ignition switch are located at the upper right side of the steering column. The electrical switching portion of the assembly is separate from the key and lock cylinder. The electrical switch portion is hidden inside the steering column. The electrical switch portion and the key and lock cylinder synchronize and work in conjunction through the action of the mechanical assembly between the 2 parts.
Passlock?"¢ Sensor
The passlock?"¢ sensor is inside the upper right side of the steering column. The passlock?"¢ sensor contains 2 hall effect sensors. The tamper hall effect sensor is on the top. The security hall effect sensor is under the tamper hall effect sensor. Both of the hall effect sensors monitor the magnet of the lock cylinder through an opening. The tamper hall effect sensor is physically placed on top of the security hall effect sensor. This arrangement enables the tamper hall effect sensor to engage first if an intruder attempts to bypass the passlock?"¢ sensor by placing a large magnet around that area of the steering column. There is a tamper resistor inside the passlock?"¢ sensor in order to help prevent tamper to the system. Passlock?"¢ equipped vehicles have a selection of 10 different security resistors ranging from 0.5K ohms up to 13.6K ohms. Installing one of the security resistors inside the passlock?"¢ sensor will generate a unique passlock?"¢ code. All 10 combinations of the passlock?"¢ sensor have the same part number. However, you cannot simply replace the passlock?"¢ sensor and expect the system to operate properly. Always start by performing the Diagnostic System Check first and following the instructions.
SECURITY Telltale
The SECURITY telltale appears on the message center inside the instrument cluster. If the SECURITY telltale flashes or if the SECURITY telltale lights continuously during the vehicle operation, refer to the system diagnosis.
Fuel Lockout Cycle
The Passlock?"¢ system has a lockout cycle of approximately 10 minutes. Once the vehicle is in the lockout cycle, the vehicle remains in the lockout cycle for 10 minutes, even if the ignition switch is turned from the RUN position to the OFF position.
The Passlock?"¢ system uses the lockout cycle in order to synchronize all of the Passlock?"¢ components when any Passlock?"¢ related part is changed. The Passlock?"¢ system requires 3 consecutive lockout cycles in order to complete the 30 minute learn procedure for a changed component.

check with code scanner to see if it is passlocked can barrow with deposit from auto zone the passlock will only turn off fuel with starting fluid it should run for a few sec.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/mike_9693b5ad75773352

Hello: You could have one of two problems: Either you have a intermittent passkey lock cylinder or a worn our ignition switch. You might go to Auto Zone and have the system checked for codes, If its a passlock problem there should be codes. I would think it might be the ignition switch if the truck quits running. Due to age and mileage it could be both.

It could be one of two things,,,This is a common L-series concern.
The Passlock is attached to the steering column behind the steering wheel,its what the ignition lock cylinder slides into,,,the passlock goes bad and does not read the correct voltage and causes the security light to come on and a no start intermitently,,,
can also cause a wrench light,,,
the other cause could be the BCM or body control module,,the go bad alot,and cause a no start and a security light,,,,you need to get the codes check in the car to know which way to go,,,,its a 50/50 shot they both go bad alot,,,,but i need to know the codes in order to have a better idea
hope this helps,,,,if its either one its gonna need to be programed before it works after replacing the bad part

security light flashing??

if it is then you have an issue with the passlock system. most commonly found in the key cylinder sensor. change and then reprogram sensor into BCM and problem will be solved

Is there a security light on, if it is then you have the anti theft working thinking someone is trying to steal the car. If you have the second ignition key's with you try it.  If not try this, it takes about 30 min to do. 30-Minute Learn Procedure 1. Turn ON the ignition, with the engine OFF. 2. Attempt to start the engine, then release the key to ON; the vehicle will not start. 3. Observe the SECURITY tell tale light. After approximately 10 minutes, the light will turn OFF. 4. Turn OFF the ignition switch, and wait 5 seconds. 5. Repeat steps 1 through 4 - two more times - for a total of 3 cycles of 10 minutes. 3x10 = 30 minutes. The vehicle is now ready to relearn the Passlock Sensor Data Code and/or passwords on the next ignition switch turn from OFF to CRANK Important: Turn the Ignition Switch OFF. The vehicle learns the Passlock Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle. 6. Start the engine. The vehicle has now learned the Passlock Sensor Data Code and/or password. 7. With a scan tool, clear any DTCs if needed. History DTCs will self clear after 100 ignition cycles. Without a scan tool you may have momentary starter interruptions while history clears itself. Good luck and hope this helps, keep me posted, be glad to help

try this it might work, turn key to on and let set for 15 mins or so, shut key off and try to start, had this happen with passlock systems.