anti theft system

No, it uses a pass-lock sensor built right into the ignition key and tumbler.

The most common failure is the pass-lock sensor itself and I can give you a way to bypass that but the rest of the system must remain operational.

Here is how you can bypass the sensor:

Go buy a 2.2k (2200 ohm) ohm resistor at an electronics store. Go to radio shack and just get one as close to that as you can. Remove the covers on the steering column and locate three small wires at the lock cylinder. Cut the yellow wire and the orange/black wire or on some vehicles, it is the yellow and black wires. Solder the resistor between those wires. Tape it up and put the covers back on and follow this relearn procedure. If this does not work you have a wiring problem in the steering column.
Thirty Minute Re-Learn Procedure
1. Turn on the ignition, with the engine off.
2. Attempt to start the engine, then release the key to on (vehicle will not start).
3. Observe the security telltale, after approximately ten minutes the telltale will turn off.
4. Turn off the ignition, and wait five seconds.
5. Repeat steps one through four two more times for a total of three cycles/thirty minutes ( the vehicle is now ready to relearn the pass-lock™ sensor data code and/or passwords on the next ignition switch transition from off to crank).
Important:
The vehicle learns the pass-lock™ 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 pass-lock™ sensor data code and/or password).
7. With a scan tool, clear any DTCs if desired (history DTCs will self clear after one hundred ignition cycles).

Electrical problem
1996 Pontiac Sunfire 4 cyl Two Wheel Drive Automatic ? miles

We have a sunfire that the anti theft system keeps locking up and leaves me stranded. is there a way to by-pass the system. this is our only vehicle and due to the fact that I am battling breast cancer and my hubby just had major back surgery we cant afford to put it into the shop. Please help with an answer. I do have some one who can work on the car but he doesnt have the knowledge for this problem.

I would just reset the system. Remove the negative battery cable and turn the ignition on, then reconnect the battery and the system will reset here is a guide that can help as well.

https://www.2carpros.com/articles/how-to-reset-a-security-system

Please let us know if you need anything else to get the problem fixed.

That worked perfect thanks for the tip, I love this site.

Please use 2CarPros anytime, we are here to help. Tell a friend please.

Cheers, Ken

How do i bypass a factory theft system in my car? It won't start.

The entire system cannot be bypassed anyway. The key sensor can be bypassed but unless that is where the problem was. it won't help. The rest of the system has to be operational.

how do i bypass the anti theft switch? car starts but runs only for 15 30 seconds and anti theft lite comes on and shuts car off......very frustrating

You cannot bypass the system. It needs to be operational and you need a Tech2 scan tool to be able to diagnose the problem.

mines needed the passlock sensor, which was failling. its in the ignition switch. with the resistor is built in. the sensor wasnt communicating with the resistor hendering the info to the module, shutting down the car. the part is 75 at partsgeek.com. or the resistor could be failing. your key probably wouldnt have a chip. BUT if it does, look at youtube video nerdboytv and go from there.

Please don't confuse the poster. This car has a Passlock system that doesn't use a resister or a key chip.

ok, if it has the passlock system, then a passlock sensor COULD BE replaced then. bypass passlock sensor @ autozone, oreilly, partsgeek. i said probably wouldnt have a chip also, read expert.

I'll tell you again. This system uses no chip, no resister, and I'll bet you have no idea how to bypass this sensor. This system isn't shutting down at initial start up as an improper Passlock code would do so it needs to be diagnosed as first posted and stop confusing the poster with misinformation.

I chipped out the ignition cylinder tried to start the car and it now it wont start. I am going to add a key style toggle switch will I need to bypass the anti theft system if so how?

You cannot do that. The immobilizer is engineered right into the operating system and cannot be eliminated.
Replace the lock with its correct components.

I have a 1997 sunfire the starter wants to keep running after the car is started and when u unhook the battery to turn the car off it quits but with the key in the off position u can hook the battery back up and the starter will constantly turn trying to start the car. I tried to bypass all that and put a toggle just on the starter and it would start and work right for bout five secs then the theft system would come on snd shut the car off. can u please tell me how to fix this I have already burnt up two starters trying to fix it.

If you need help with something, please start a new question of your own. This one belongs to someone else.

is there any way to bypass theft system

No, if the system is factory.

My husband was working on the car, and put the key in there, turned to on, and moved the wheels. Guess who left it in the on position and activated the Passlock? That lil rascal cuts the fuel off to the engine, if it gets activated, and boy, is it ever activated. Car was working fine,until he did that. I let him do the brakes, and ....whoo boy. When my brother was alive, he was a Master Certified Mechanic, and he taught me a lot about cars. So i tried the following.... 1) Checked fuses ( ok) 2) Checked fuel pump( ok) 3) checked gas filter(ok) 4) poured a small amount of fuel into throttle body, and it DID start, but cut out immediately, which is when i knew the Passlock was up-n-at-em (rolls eyes). Then i tried the following ..1) opened door with remote,locked car door while open,closed door, opened door with key 2) put key in ignition, turned it to on position, left it for 10 mins, turned it off, and repeated process 2 more times. THEN tried it for a longer period. Nothing worked, and i've already replaced a functioning fuel pump, AND the gas filter. Any ideas, before i wool the head straight off my husband for leaving the key in the ignition in the first place? And NO, no fuel lines were damaged, while the car was up on the jack - i checked. My brother would be either laughing at all of this, or cursing up a blue streak. I'm heading towards the blue streak myself.
I also ran the computer diagnos on it, and no codes came up. Starting motor is working fine. Battery is fine as well. My brother left me all his Snap-on and Ingersoll Rand tools( let's just say i have 4 full chests of tools) so i'm ready to haul the darn thing apart, i'm so frustrated. If i knew how to disable the Passlock, i would ...grrrrr. I let HIM at the car, because he likes to tinker with it, and i was never fond of beating a tire off the car with a 10 lb sledgehammer, because the lug nuts were seized up( i can do it, just don't like it). Your answer just may save him from getting a strip torn off his hide, verbally :D

You only have one chance here and that is the relearn procedure. If this doesn't work, it means that there is a hard fault and your will need a Tech2 scan tool and I'm will to bet he didn't leave you one of those. Your going to be stuck with either the dealer or electrical specaility shop.



30 Minute Re-Learn Procedure
1. Turn ON the ignition, with the engine OFF.
2. Attempt to start the engine, then release the key to ON (vehicle will not start).
3. Observe the SECURITY telltale, after approximately 10 minutes the telltale will turn OFF.
4. Turn OFF the ignition, and wait 5 seconds.
5. Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes ( the vehicle is now ready to relearn the Passlockâ„¢ Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK).
Important
The vehicle learns the Passlockâ„¢ 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 Passlockâ„¢ Sensor Data Code and/or password).
7. With a scan tool, clear any DTCs if desired (history DTCs will self clear after 100 ignition cycles).

Chuckle! No, he didn't but there's no problem in getting any tool/sensor/hydralic lift etc, that's on the market. All i'd have to do is ask, and that's the problem. I just hate asking his buddies for any favors, because they get very... upset, remembering how he died, in front of them, under that walking beam bushing on that rotten big truck. I look enough like him that i see the memory in their eyes, every time i talk to one of them. If they knew about the problem, they'd be over in a flash :s I don't like using anyone,even if they offer the help, and would rather do it myself. I'll try this, tomorrow, in daylight :) i don't think i waited after turning the key off, any of thetimes i tried

This is not something the average mechanic will have. It is a factory GM scan tool and with it costing $10K plus and only being good for GM, it's not that common in the aftermarket.

i tried what you said, had a bit of patience, for a change, and yes it worked! YaHOO !! :D one of the guys dropped by, just as i was closing the hood :O Thank you so VERY much for all your help!! I'd have hated to be at it when he showed up - i'd have been glared at, AND read the riot act, big time, for not asking for help. Once again, THANK you! JUST in time!! :D
I have got to ask about that sensor though....NOW you have me CURIOUS!! LOL Heck with techie toys, gimme techie mechanic gadgets any day :D

That was very nice of you to find that for me, hun :) Thank you. I should have been a car mechanic, instead of working in my particular brand of " body " shop. The boys usually show me how to use any diagnostic equipment, so they ought to get a kick out of seeing that lil beauty. I was looking at one,today.
Most of my coworkers go around with a first aid kit in the car. ME? I carry booster cables, a car emergency kit, first aid kit AND an AED. Jumpstart/repair kits available for cars AND people!Once again, thanks hun!!

Electrical problem
1996 Pontiac Sunfire 4 cyl Two Wheel Drive Automatic

My sunfire will not start and the passlock light is on. Can anyone tell me how to reset or disable this?

GM PASS LOCK RELEARN- Ignition to "run" position, try to start and let key return to "run" position.
Approx ten minutes security light will go off
Turn key "off" and wait 5 seconds
Repeat 2 more times for a total of 3 relearns.
Turn key off, then start it.

daughters car alarm goes off and than does not start.what is causing this.

GM anti-theft systems are real effective at keeping owners out of their cars. They don't do much to deter thieves. One common problem is broken wires to the sensor in the ignition switch.

Changed the ignition lock cylinder did the ten minutes relearn procedure security light went out car still won't start do I need to put the 2 ohm resistor on the yellow and black wire and redo the relearn procedure or is there something else I can try

you may have to do security relearn 3 times.