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Finally a cheap passlock fix!
CF Active Member
Joined: Jul 2015
Posts: 172
Likes: 0
From: SE Michigan
Can you send me the diagram pleease of the bypass at isakclouse@gmail.com. i already took ignition switch out wich connectors in particular should i look for coorsion? My yellow wir gets 12v and black zero testrs resistance between yellow wites then spliceds resistors equal to value into black wire but still no start, jumped starter and fuel rail both work mabe no spark idk what to do security light flashing
If your security light is flashing you need to try the relearn procedure. A tip, while you are doing it either set the parking brake or hook up a battery charger so the lights don't kill it. If the light is still flashing after the 10 minute relearn try the 30 minute, and if that doesn't work your going to need professional help.
CF Beginner
Joined: Nov 2016
Posts: 2
Likes: 0
This may not be the same issue as yours, but mi 98 GMC would start and die. The computer said the ignition control module was bad, so i replaced it. It still did not start so after reading a few post i went and had a new key cut and my truck started and now runs well. I hope this helps.
CF Beginner
Joined: Apr 2010
Posts: 11
Likes: 0
2002 impala purchased new. Last week I got my new ignition switch module and put it in. Working fine. I pulled the old one and removed the key cylinder after unplugging all the wire harness connectors. The white plastic back piece can be removed with a little prying. The reed contacts are located there. 3 months ago I had pulled it apart and cleaned the contacts. Worked good for a little while. They are pretty micky mouse and I probably was not aggressive enough to work longer.
In 2003 the dealer put a new body control module in. this worked a year or so. I put in a bypass module like they use to put in remote starters. this worked a few years. I hope the new switch will work a few years. Everything is connected and a little weakness in one link just kills you and now matter what you do something else will weaken latter. Don't ever think you have fixed it forever.
In 2003 the dealer put a new body control module in. this worked a year or so. I put in a bypass module like they use to put in remote starters. this worked a few years. I hope the new switch will work a few years. Everything is connected and a little weakness in one link just kills you and now matter what you do something else will weaken latter. Don't ever think you have fixed it forever.
CF Beginner
Joined: Jul 2017
Posts: 1
Likes: 0
I'm having the security problem on my 04 impala. Can you please send me the fix to jmschwiderski@gmail.com
Had this done a couple of weeks ago. Hasn't acted up once, security hasn't come on at
all either. Hired our tractor mechanic to do it. Said 2 contacts were burnt on key switch.
Used sand paper to clean them, and good to go. Cut and pasted from another site:
I just fixed my 2002 impala security light issue. It cost me 2 hours, no money. Here is how the system works. The passlock sensor and the ignition switch are in series. When you turn your key you generate a low current read by the body control module. If the current generated is out of range the BCM won't recognize the signal and your car won't start for 10 min. There could be different reasons why the signal is out of range. On most of the cases the ignition switch contacts are burned out, and this will cause a voltage drop on the contact so the signal getting to the BCM is going to be lower than usual so it will be out of range. Take your ignition switch out (if you don't know how send me your e-mail (believe me I'm not looking for e-mail addresses I just need to scan the instructions, since I have them only printed out) and I'll send you detailed instructions for free. Once the switch is out remove the cover on the back of the switch (it is clipped on, all you need is a flat head screwdriver). Once the cover is removed you should see 5 fairly big electric contacts. I bet at least one or two are burned out. Clean them with fine sand paper until their surface is clean and flat and make sure the steel springs pressing the contacts together are tight and are pushing the contacts firmly. If not, using pliers bend them to get good contacts. Reinstall the switch and your car should start every time. If the contacts are really bad you might have to change the ignition switch.
I know dealers want to change every part on the car so please do not let them change the passlock sensor. The passlock sensor is a hall sensor and there is no reason for the sensor to go bad.
all either. Hired our tractor mechanic to do it. Said 2 contacts were burnt on key switch.
Used sand paper to clean them, and good to go. Cut and pasted from another site:
I just fixed my 2002 impala security light issue. It cost me 2 hours, no money. Here is how the system works. The passlock sensor and the ignition switch are in series. When you turn your key you generate a low current read by the body control module. If the current generated is out of range the BCM won't recognize the signal and your car won't start for 10 min. There could be different reasons why the signal is out of range. On most of the cases the ignition switch contacts are burned out, and this will cause a voltage drop on the contact so the signal getting to the BCM is going to be lower than usual so it will be out of range. Take your ignition switch out (if you don't know how send me your e-mail (believe me I'm not looking for e-mail addresses I just need to scan the instructions, since I have them only printed out) and I'll send you detailed instructions for free. Once the switch is out remove the cover on the back of the switch (it is clipped on, all you need is a flat head screwdriver). Once the cover is removed you should see 5 fairly big electric contacts. I bet at least one or two are burned out. Clean them with fine sand paper until their surface is clean and flat and make sure the steel springs pressing the contacts together are tight and are pushing the contacts firmly. If not, using pliers bend them to get good contacts. Reinstall the switch and your car should start every time. If the contacts are really bad you might have to change the ignition switch.
I know dealers want to change every part on the car so please do not let them change the passlock sensor. The passlock sensor is a hall sensor and there is no reason for the sensor to go bad.
CF Beginner
Joined: Aug 2017
Posts: 3
Likes: 0
Hello, tgman1 here, I would like to first (taking the time to solve this hidden issue) THANK YOU :-) I am a disable vet and I need my car to run again (VA Appt. etc..) can't afford a new car( or a used one) and I like to challenge this issue myself before I go taking away funds for home (I have a disable son). So if you are willing, I would like the diagram and fix this my self. I got new Ignition switch (doesn't work), new battery (did not correct issue), look on YouTube (NO Answer), and Banging/Hammering the HELL out of it doesn't work either. Only thing will show is an Engine Light (NO SECURITY LIGHT, NO FLASH) from time to time (1 out of 10 times). Relearn (*I tried for an hour), sucks, because it did not work. If I can replace an Radio w/ an aftermarket radio, I can FIX this as well. Just glad some one cares enough to take time and fight for the little guys. Thank you for your time and efforts. -TGman1- my email is jag76drg68@hotmail.com
Last edited by tgman1; Aug 14, 2017 at 3:30 PM. Reason: spelling
CF Beginner
Joined: Aug 2017
Posts: 3
Likes: 0
Hello, tgman1 here, I would like to first (taking the time to solve this hidden issue) THANK YOU :-) I am a disable vet and I need my car to run again (VA Appt. etc..) can't afford a new car( or a used one) and I like to challenge this issue myself before I go taking away funds for home (I have a disable son). So if you are willing, I would like the diagram and fix this my self. I got new Ignition switch (doesn't work), new battery (did not correct issue), look on YouTube (NO Answer), and Banging/Hammering the HELL out of it doesn't work either. Only thing will show is an Engine Light (NO SECURITY LIGHT, NO FLASH) from time to time (1 out of 10 times). Relearn (*I tried for an hour), sucks, because it did not work. If I can replace an Radio w/ an aftermarket radio, I can FIX this as well. Just glad some one cares enough to take time and fight for the little guys. Thank you for your time and efforts. -TGman1- my email is jag76drg68@hotmail.com
CF Beginner
Joined: Aug 2017
Posts: 3
Likes: 0
Hello, tgman1 here, I would like to first (taking the time to solve this hidden issue) THANK YOU :-) I am a disable vet and I need my car to run again (VA Appt. etc..), can't afford a new car (or a used one) and I like to challenge this issue myself before I go taking away funds for home (I have a disable son). So if you are willing, I would like the instructions/diagram and fix this my self. I got new Ignition switch (doesn't work), new battery (did not correct issue), look on YouTube (NO Answer), and Banging/Hammering the switch doesn't work either. Only thing will show is an Engine Light (NO SECURITY LIGHT, NO FLASH) from time to time (1 out of 10 times). Relearn (*I tried for an hour), sucks, because it did not work. If I can replace an Radio w/ an aftermarket radio, I can FIX this as well. Just glad some one cares enough to take time and fight for the little guys. Thank you for your time and efforts. -TGman1- my email is jag76drg68@hotmail.com
CF Beginner
Joined: Aug 2017
Posts: 1
Likes: 0
Help me send me how to bypass email babydjgilbert8@gmail.com
ok first off changing the ignition switch and tumblers will do absolutely nothing sorry if you have already done this. there are three main components to the passlock II system the passlock sensor, the BCM, and the Ecm and of course the wiring in between. Odds are if this keeps happening and there is no other problems such as door locks freaking out trunk release just goin off then it's not the bcm if you do the relearn feature and it works the it is also not the Ecm. so you are left with the 3 wires that run from the bcm to the passlock sensor.odds are the passlock sensor is bad. now there are two solutions either go to the dealer and have the sensor replaced or bypass the system for good. any respectable mobile electonics installer should be able to do this no problem it takes me about 20 mins and i personally charge 40 dollars to do so hope this helps also if you are mechanically inclined in electronics i can send a diagram on how to bypass it yourself hope this all helps
CF Beginner
Joined: Oct 2017
Posts: 1
Likes: 0
Diagram
ok first off changing the ignition switch and tumblers will do absolutely nothing sorry if you have already done this. there are three main components to the passlock II system the passlock sensor, the BCM, and the Ecm and of course the wiring in between. Odds are if this keeps happening and there is no other problems such as door locks freaking out trunk release just goin off then it's not the bcm if you do the relearn feature and it works the it is also not the Ecm. so you are left with the 3 wires that run from the bcm to the passlock sensor.odds are the passlock sensor is bad. now there are two solutions either go to the dealer and have the sensor replaced or bypass the system for good. any respectable mobile electonics installer should be able to do this no problem it takes me about 20 mins and i personally charge 40 dollars to do so hope this helps also if you are mechanically inclined in electronics i can send a diagram on how to bypass it yourself hope this all helps
could you please send me the diagram I would greatly appreciate it