How To Permanently Disable GM PassLock System

Purpose

The following instructions will allow you to disable the PassLock security in quite a few GM Vehicles.

  • This will allow you to install a remote starter and not have to purchase a bypass.
  • Avoid Costly repairs for an already broken Pass Lock System.
  • Disable Pass Lock system to prevent from being stranded in the future.

Requirements

A digital ohm meter (optional)
T25 Screw Driver (optional)
Alligator Clips (optional)
Screw driver or other tools for removing interior panels
1/4″ Drive 7mm or 9/32 socket and socket driver

Procedure:

 This tutorial varies depending if the ignition is located:

On the dash close to the radio

dashmounted

Is mounted in the steering column

steering_column

If your ignition is located in the dash then you will be removing the panels on the passenger underside (toe board) of the dash. The BCM (Body Control Module) is there and so are the wires we need to get too.

If you ignition is located in the steering column then you will be removing the driver side kick panels of the dash AND the clam shell around the ignition held in with torx screws.

For Cavalier and Sunfire Owners you ONLY have to remove the clam shell around the ignition that’s held in with 3 bolts.

Depending on the vehicle we will be looking for 3 wires bundled together their colours are either:

(Group1)Red/White Yellow Black
(Group 2)Red/White Yellow Orange/Black
  1. Remove the appropriate dash panels to get to the wire harness.
  2. Locate the Pass Lock 2 Wires, they will be coming out of the ignition OR on the BCM they will be located in the grey connector, Pin A6 is your yellow wire, and pin B6 will be a black wire(they should be right beside each other).
  3. Strip some of the wire insulation off the black wire, leaving it bare so you can test and solder to it later. DO NOT CUT THIS WIRE!
  4. Now cut the yellow wire, make sure to leave enough on both ends to give yourself something to work with. Strip both of the cut ends for testing.
  5. Take your digital ohm meter and put your negative probe on the black wire that you stripped back earlier. Put the positive probe on the yellow end of the wire that leads BACK to the ignition. Use alligator clips here to help the probes grab the wires.
  6. With the probes hooked up turn the ignition to the run position. Don’t try to actually start the vehicle, it won’t run anyways :). Read the ohm reading of the meter this is the resistance that we need to create to fool the PassLock security. Turn off the car.
  7. When selecting a resistance don’t worry about being dead on sometimes being close is good enough. If you can’t find something anywhere near to what you read on the ohm meter you have the option to use a resistor between 0.5K ohms up to 13.6K ohms.
  8. With the probes disconnected, take the resistor you selected and attach one of the ends to the black wire and then attach the other end to yellow wire that leads away from the ignition (goes to the computer).  Apply black electrical tape to the yellow wire end that goes to the ignition, we don’t need it anymore.
  9. With the resistor connected try and start your car, if you matched the resistance the car will start on the first or second try.
  10. If it starts then SUCCESS! Solder all your new connections. Tape up your bare wires and re-assemble your dash you’re done 🙂
  11. If it doesn’t start don’t freak out. You will have to do the factory relearn procedure(really easy)

10 Minute Learn Procedure 

  • Starting from the off position.
  • Attempt to start the engine, then release the key to Run position (vehicle will not start).
  • Observe the security light located in the instrument cluster, after approximately 10 minutes the security light will turn OFF. Turn OFF the ignition, and wait 5 seconds.
  • The vehicle is now ready to relearn the Passlock Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.

Important
The vehicle learns the Passlock Sensor Data Code and/or resistance on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.

12.    Your all done, Solder all your new connections. Tape up your bare wires and re-assemble your dash you’re done 🙂

276 Comments

  1. For anyone who cares… don’t blindly print this page out.

    There are -89- pages of effing comments due to the site’s format. Just print the first 6 pages so that you don’t walk into the printer room later and stare in disbelief at the effing toner & paper you just pissed away.

    1. For what its worth, Thanks. I’ve corrected the issue with the comments.

  2. Going to throw this out there in case anyone might be able to help out with some general info:

    I’ll be attempting this on my 1996 pontiac sunfire. The theft system was triggered when a street youth broke into my car and severed most of all the wiring in my steering column thinking they could hotwire my ride and take off with it. When that didn’t work, they forced a screw driver into my ignition and totally wasted the whole freakin thing. Father in law tracked down a new column and jacked it into my car but now the vehicle will only crank and power down immediately (theft system is active of course, in a terribly ironic turn of events). Just wondering if this bypass will work if everything has been hooked back up correctly. Is it only a simple matter of doing the re-learn process? It has not worked for me thus far, wondering if introducing this fix to the situation will be constructive?

  3. Will this work on 08 and 2500hd 6.0l gas….
    Thanks Jonathan

  4. Thanks for perfect solution. installed resistor, switched key on for 10 min. re-learnprocess, then started car. theft light in dash is off.

  5. Ok i have a 2001 silverado 1500 ls 5.3l v8 and i tried to program a aftermarket fob with no luck i read some where online that my keyless entery receiver might not be working so today i went to my local pick n pull and got a receiver out of a 2000 chevy 1500 i came home took dash apart un hooked the exsiting receiver took it out and put the other one from junk yard in. Put evert thing back together tryed to program fob and nothing just like the stock one!! So i figured oh well it’s not gonna work so i started my truck and after a couple seconds truck sputterd and died!!! I started it again and it died!! Now it wont start at all!! This has never ever happend to me in this truck!! So i thought it has to be the receiver from junk yard so i took dash apart again and put the original receiver back in! And my truck still wont start!!!! I tried the relearn program, were you put key in the on/run for 10 mins turn off for 10 sec, then on/run for 10 mins then off again for 10 sec then on again for 10 mins then off 10 sec then try to start and it just turns over and over no start!!! Also on the 10 min relearn reprogram trick all forums say that when you start the reprograming that the security light will flash or stay on solid, when the key is on and to wait for security light to stop flashing or turn off which takes 10 mins. but when I turn key on only the red battery light comes on flash’s once and stays on. and is also where security light is it is the same window. or the battery light comes on solid for 6 seconds then security light flash’s for 6 seconds the it keeps repeating over and over! I don’t know why this is? because I have a battery charger hooked up to battery. The truck ran perfectly that day and always has till i changed out the keyless entery receiver please can any one please help!! Thank you so much for any help!!

  6. When checking resistance from from the Orange/ Black to the Black wire of the ohm meter and the Red wire of the Ohm meter to the Yellow that goes to the ignition, NOT the BCM, I also do not get any reading. Does this mean the switch is bad or what should I do differently?

    1. I’m getting the same thing steve. Any progress?

      1. Never have figured it out yet. Might have to take it in. Not getting any help here. 🙁

  7. Do you think this might work on an 04 Pontiac Gran prix?

  8. Got stranded in a parking lot for an hour today having this issue again. And I couldn’t pull the ohms correctly for a 2001 silverado 5.3 liter. If anybody knows the correct resistor value I’d certainly appreciate it.

    1. I’m working on an intermittent stalling issue myself and am doing the bypass on a 2001 GMC Sierra 1500 4×4 5.3 and the resistance I got was 1.35 ohms.
      Your mileage may vary but I hope this helps.

  9. I gave this fix a try and had no luck. I got no ohm reading from yellow wire. When I soldered it back together I got 1300 -1400. Granted I likely had wrong resistor. I pulled a 1/4 watt from old vcr and I gather the resistance to have been 3400. My car will not start and I was wondering if a dead pass lock sensor will cut power so this isn’t going to work? Also, I saw a tutorial where it seems the guy was saying to place resistor in yellow wire. He did not talk about connecting it to black wire. This makes sense? Or even a 3 way connect….?

  10. Le monte un arrancador remoto a mi GMC ENVOY 2002 y no prende busque los cables passlock y tampoco que podra ser

  11. Hello
    You said :The following instructions will allow you to disable the PassLock security in quite a few GM Vehicles.
    My question is:
    This will work on a 2004 Gmc Canyon with Passlock II security system?

    I will appreciate your answer
    Thank you.

  12. Will this work for a 2005 chevy cavalier?

  13. 2000 yukon 5.3 vortec. I dont have a black wire, have yellow, orange w black stripe, red w black stripe. Whuch do i connect the yellow to? Thx

    1. My blazer is the orange/black to the yellow

    2. Hey! Kevin, your orange w. black stripe = (black wire).

  14. I have had this problem on a 2003 GMC savanna for approximately four years now. It was diagnosed by some repair shop and supposedly fixed but never worked right. I still have the security issue. I would always turn the ignition off, for 10 minutes or less, waiting for the security light to go away. Recently I accidentally put the vehicle in neutral after security light came on and it started. Ever since I’ve had the security light issue, my resolution has been to stick it in neutral and start the vehicle and it has worked. Give it a try it cost nothing.

    1. Jason… I have been having a passlock issue for at least 6 months and tried taking out fuses and everything else but nothing worked as the issue would keep returning. Today the car would not start and lo and behold I put it in neutral and it started on the 1st try! Thanks for your mention. This could save me 10 minutes every time it happens if it continues to work!

      1. I have noticed that it does work but only occasionally. So feel good in only being frustrated half of the time. Bwahahahaha.

  15. OK so I cut the wires to the ignition antitheft lock system my boyfriend and i were fighting i didjt want him to take my car so i clipped them i needed to rewire everything and know the lock wont go away 06 Chevy cobalt

  16. I am working on a 2000 k3500 Chevrolet with a 5.7 engine. I found the passlock wires , and I have a yellow a red white , and a orange black. My question is do I use the orange black wire and connect it to the yellow wire going back to the ecm. Thanks.

  17. I have a 98 Sonoma chassis that I put not older chev cab on to it, 98 somoma ran perfectly until I did the switch, security lights all over the dash come on, checked fuses, BCM,VCM and PCM, checked grounds and loose wires, security light stays on all the time even with the key out. I have 3 keys and none are chipped. Battery is fine, truck turns over and then dies in seconds just like everyone else’s story on here. Like I said truck ran fine before. I took out the ABS A/C, radio, seat belts,, none of which will effect how’s the truck will run, but everything to do with security. I even bought the newrockies bypass module and performed the relearn several times and still nothing. , so i’my thinking it’s a loose connection somewhere, but if anyone out there has some info for me let me know. I’ve been spending so much time building this truck that it’s affecting my family and I really need to get this past me.

  18. I have this same problem but here is the funny part, I’m getting a 9.650 reading on the yellow wire going back to the BCM, no reading on the yellow going to the Ign. so I tried a 10k resistor and still nothing. What am I doing wrong.

    1. Al, I’m no expert but just finished this fix on my neighbors 2002 Malibu.
      You say you took a reading on the Yellow back to the BCM,
      You should be checking the Yellow you cut back to the KEY switch. from the
      Black wire you’ve “bared” but not cut. Turn the key to ON “not to crank” and
      this will give you the “value” your looking to replace with the resistor .
      I called my local TV / Stereo repair shop and the gave me a Whole Range of
      resistors from .0510 to 13.5 K Ohms and even marked the and sandwich between Tape !
      For $ 3.00 !
      My reading of the “KEY” yellow to the black was .615 so I used the .510 closet I had …
      and wallah ! Fired up first try ! Theft light was on but went out at 2nd start .
      Hope this helps
      Sincerely Mark B , AKA The Dude

  19. Will this work on a 2008 Chevy Trailblazer?

  20. Will this work on a 2004 Malibu 2.2 I have tried every other method with no luck

  21. I will let you know if I can do what I have been shown. Thanks

  22. You say it works on most GM
    vechicle’s , how about 2002 SATURN Sc1 ?

  23. Okay so i have a 99 Chevy silverado 3500 with the 6.5 turbo diesel. Truck was running great until a starter wired melted and an blowing ignition fuses everytime i would turn the key. that problems fixed but now when i try to crank the truck it will turn over and run for about a 1 second and turn off like fuel is getting shut off, securty light stays solid, have tried realern didnt fix it. Will this bypass fix my problem? Or do i have another isssue?

    1. hello i am having the same problem with mine can you tell me if you got yours fixed and what was it

  24. I’ve been trying to get a 2002 6 litre LS engine to run as stand alone.I had to connect the wiring harness from cab for it to run after I start it . As soon as I plugged the radio fuse in,it was alive and running very well,i have it bolted down to a strong 4 wheel cart. I need to know how I can trick computer for engine to run without the rest of the wiring from cab .some how run engine on the coils ,injectors ,fuel pump and the other sensors just for the engine to run in “stand alone ” without the body control module . Ive been working on possibly putting the 6 litre LS in my 68 Camaro ,which has a .060 327 in it now and run it on 114 octane gas with 6:13 gears in the 58 Pontiac differential .
    Hope some one has good news to help me out before I drive myself crazy with schematics and body control modules.Stand alone sure was a good idea ,but wasn’t expecting the “passlock” to be screwing with me .Till then thxs for your time,

  25. What’s going on when you’re your meter doesn’t show any resistance at all when you connected to the wires? Are you supposed to have the key turned on or the key turned off or the key out of the ignition

    1. Check meter. Should be set to 20k
      I had to turn key all the way – as trying to start truck to get resistance to show

  26. I have a 98 chevy 2500. I’ve tried the resistor but no luck. I bought a Xpresskit to bypass it. No luck. I’ve tried several times to do the 10 minute reset. No luck. Please help!!!!

  27. will this work on a 2003 impala? Ignition on dash ?

  28. Hi. I have a 1999 GMC Sierra two wheel drive automatic, air cond, cruise control with a 5.3 V 8. My security system took a crap and it took me 7 days to figure it out. To make a long story short i found the yellow wire and the orange with a black stripe in the wire running down from the switch and through the steering column. ( the orange with black stripe is also the black wire they tell you to look for ) Anyway, mine called for 520 ohms when i did the test. What you have to do is from your ignition switch there are wires plugged into the sensor on top of the switch. Make sure you have the two colors i said. There is a red and white one there also but make believe it’s not there because you won’t use it at all. Follow the two down to where you can work with them. Cut the yellow wire in half make sure you have enough room on both ends to work with. The orange with black stripe just strip the coating off enough to solder to it. I used a 470 ohm 1/2 watt and three 15 ohm 1/2 watt because i could not find a 520. I know that only adds up to 515 but when you check it with a meter it will show 520, mine did anyway. You need to solder them in one length like a rope. Solder one end to the yellow wire that goes to the dash not toward the switch. That one you will tape off. The other end solder on the orange with black stripe. When you do that you might have to do that 10 minute thing to match up to your ECM. You might have to do that 10 minute thing 3 times. There are other people on here that you can read to tell you how to do that 10 minute thing. It takes to long to explain. I am only telling you this because if you have a truck like mine i am trying to save you time. Yours might be different and you might have to follow a step by step instruction.

    1. that is very well written and explained cant screw that up.

  29. Says here only to cut and wire black and yellow but you have 2 black ends.
    Do you wire the resistor 1 end to the black and 1 end with black and yellow together?
    My wires on a 2001 Chevrolet Express 5.7L van has the red/white, orange/black, yellow.
    Do you twist 1 black or orange/black and yellow wire together and test for resistor to the
    other black or orange/black wire?

    1. Pa Ej you don’t cut the orange and black wire at all….you just strip the coating so that you can solder the one resistor end to it. The yellow wire you cut in half and solder the other end of the resistor to the end of the yellow wire that goes to the computer. The other end of the yellow wire that goes back to the switch tape up so it don’t spark against any metal. If you did everything right it should start. I had to do that 10 minute test three times so it could jive with the ECM. Read some of the stories on how to do it right but the way to wire the resistor i told you is the right way. If you can’t find the right ohms you might have to buy a few of them to get the number you are looking for. Just sloder them like a rope in a straight line. I hope this helps.

  30. Does it work with Chevrolet Camaro 2013 ?

  31. I purchased a O2 impala dirt cheap to fix and sell, the previous owner put a fuel filter fuel pump, ignition etc…. I have found if I reset the security system the car will run as long as I leave it running!!
    What size resistor do I need?
    How many ohms does a passlock sensor have ?

    1. It’s depends gm has 15 types of key with resistance from 350ohms to 12700 ohms? With a 5%- /+ minimum and maximum. If no reading in ohms change settings to k ohms on meter?

  32. Do u do this between the little clip on the ignition and the bottom of the ignition maybe 6inches of wire or
    Between the back of the ignition whatever the whole lume bolts to
    I tryed both and couldnt register any ohms when key was turned to on position

    1. Forget the question now my light stays steady not even a flash
      I installef an entirely new ignition and harnedd with matching key…..lightbstill on steady … Did relearn

      Thanks

      1. Sorry i have come to the conclusion that when the security light stays on steady with no flashes ever in meand your security has been disabled already, most lickly from unplugging or ripping out the 3 wires( black/orange, red/white,yellow) while the motor is running 1998 astro 4.3 my start run for 2 sec die was actually the ecm?…black box about 4×6 inches maybe 1/2 thick …..i was just about to install fuel pump and the truck started but after moving my glob of wires ( ac/heater controls)back up into the dash it wouldnt start do i tracked it to the wiggling the ecm at the plug so i just unplugged it and threw it away security light is gone truck runs better than ever ……what does it even do i thought it controled the whole car….. Apparently not mine.

  33. What if you do this and still won’t start. Started for like 5 sec and then shut off and won’t start now. Pulled a p0700 code. Got rid of the code tried the relearn but still won’t start. 04 chevy 2500hd

    1. Also what watt resistor should you be using to do this?

      1. I have not tried this resistor method but I do know a little about resistors. You won’t hurt any thing if your watt size is to big or even way to oversized . if you go to small the resistor can over heat and damage.so if I was going to try this ( I may have to real soon my car got pass lock reset trouble).quarter watt might be OK but I’m going to try a half watt resistor and if its to hot ( i doubt it )then I’ll try what ever else I got 1watt or 2 watt or 5 watt or 10 or 20 watt , what ever I can find in my tool room. As far as watts goes ,its a measurement of how much heat a resistor can dissipate continuously , in DC circuits the dc amps reading flowing through the resistor multiplied by the dc voltage reading across it equals the heat or watts that radiates off the resistor .Well good luck !

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