Re: GM Headache

jeffcoslacker wrote in news: snipped-for-privacy@no-mx.nodomain.com:

first sentence, 2nd paragraph of OP.....key wont turn

Funny, I read key w

jeffcoslacker wrote in news: snipped-for-privacy@no-mx.nodomain.com:

oh , i read the entire post. the wall he was up against at the time was just getting the key to turn to be able to find any other probs.

you have to understand the order in which he is approaching problems before you lead the poster off track.

Say Guys,

Thanks for the response...Id be screwed without it, I assure you. Personally, the last time I had to get into a key cylinder was a 90's ish Buick. I went for a good 10 years without turning wrenches as I got involved with Premise wiring for Computers/Telephone systems. As is evident in my original post, the new type of anti-theft hardware/software in cars has changed considerably since I have have stumbled back into it! To clear up a misunderstanding on the "key turning issue" Your both sort of correct at the same time. Ok, My friend tells me "Sometimes the key wont turn out of "Off" position. Well...sometimes my ass...it never even acted like it was going anywhere for me. So, while it supposedly operated some of the time for him, no go later after I darkened the door! Armed with some basic info and a dig multi-meter, Im approaching it like this: We're dealing with a PCM/BCM Key cylinder with mag field, but no sensor. So it simply sees when key is turning and grants permission to fire up systems. However, Im still baffled about key not turning in Ignition.. Short of key cylinder being simply worn out of course, I was trying to make sense of the original problem in the first place. Since some systems recognize keys as being correct for a particular vehicle, What, in East Jehosafat, is the problem with this piece of work? Could we be dealing with faulty electronic/software snufu's combined with a worn out lock. I scoured the automotive forums for answers, but didnt exactly get run over in the pontiac forum. This forum seems to have a lot more experienced eye's on the more difficult subjects. Thinking back on the history of my involvement on this vehicle, Ive observed the following or been informed: 1. A 2000 GA which had original motor burned up within a year. 2. A good used motor put in its place consiquentially (ahem...) 3. They say the car has been running great since then.4. My first sight of the conditions in which the vehicle has been cared for/maintained...Under the hood....wiring exposed in several areas for the purpose of testing ( Though... I would not leave said wiring in this shape even for a moment while trying to do a systematic problem solve ) 5.Overall apparent cond. haphazardly dishelved but workable....I think. This guy needs to be kept as far away from the interwokings of an automobile as possible.6. I band-aided the wiring for now and propose solder and shrink wrap before I sew the thing up. Every picture tells a story dont it, and this one is no exception. Ok, So where I am now, in my estimation is....When I am able to actually turn key, check for security light on IP. If present, why. Learn from researching prob. and talking to you guys what snafu might be/ prove to be. And finally, since I have butchered the ignition switch and housing trying to Exorsize it, what sort of little tidbit parts or special tools might I want on hand to put it back together (Namely, the cable assem. I spoke of and the three wire connector I plucked out of the housing ( the connector is still intact) Anything come to mind to watch out for or perhaps a sequence of problem solving that would prove helpful.

Jokes are welcome....one would have to be a little crazy to work on cars. Laughter helps get u through the rough spots.

This reminds me of a chart I read in the office of an Audio/Video equipment installer. ( A supposed substitute fuse where real fuse is not availible.) They started with foil, light wire, nails, and my favorite....A bolt was shown as a high capacity fuse...referred to as a.... Slow Burn.....

Thanks Guys for what ever you can do.....

the road

I'm still a little lost. Does it have VATS or not? If so (square chip in key) the VATS resistor has to make contact with two contacts in the cylinder or the car will not start. You can probe the contacts on the VATS chip and read the resistance, and substitute a standard resistor shunted into the wires for the VATS if doing so helps in any way (like to verify that it is disarmed while trying to figure out why the key won't turn) so if you remove the ignition lock and turn the switch manually, you still have to have the correct resistance present in that circuit...I'm no good with cylinders, my experience is mostly limited to pulling them out with a slide hammer prior to reposessing the car;), but that gets you nowhere with a VATS equipped system.

Dumb question, but the cylinder is not in a torque lock because he shut it off with the wheels turned, is it?

GM hasn't used VATS in about ten years.

PATS replaces VATS and works entirely different.

My friend's '00 Lumina has a VATS key, so I assumed this one might be similar. How's PATS work? I've been out of the shop for about 7 years now, and I'm getting farther and farther detached from what cars use anymore...and forgetting things I should really know. :banghead:

The Lumina was one of the last hold outs for VATS, even the lowly Cadavalier had PATS in 1996.

PATS is a bit too complicated to describe here, if you google "GM passlock" you should find a bunch of information.

Here's an article from Motor Age to get you started;

the link is no good...but I found some other stuff about it but I need to read it more carefully, because it basically sounds the same as VATS except the resistor is in the lock rather yhan the key (for what purpose I don't get), so that if you crack the column and try to start it with no key to complete the circuit in the lock, injectors are disabled.

Does this mean that ANY key, whether correct one or not, would suffice to complete the circuit as long as it fit in the cylinder, or is contact only made when the lock is rotated from the locked position when the correct key is used? Because otherwise any clown with a worn down key could defeat it and start the car...

Anyway...still looks like a likely spot to cause the trouble he's seeing...

(summarizing) The resistor is replaced by a Hall Effect sensor that has to send its signal it the correct point in the power up sequence. if the lock cylinder is "jimmied" the sensor is destroyed and/or it becomes very difficult to get the sensor signal timed correctly.

If the key fits the lock tumblers and the lock cylinder can be rotated, the car will start. Odds of a worn key working are slim because they keys now have more cuts, 8 or 10 IIRC.

Absolutely a likely cause. These things are getting quite notorious for failure.

i just went thru the same thing,i have a 2001 grand prix and it turns out it was the pass key 3 theft deterrent system it cost about $600 to fix at a dealer,damn dealers now i cant get the key out of the ignition!!!! they say it will cost me another $300.

'Oh no, I've already changed all that'

Don't trust ANY work ANYBODY else has 'already' done. Most folks create more problems than they fix when they start 'shotgunning' their vehicle.

Some of the worst 'messes' I've straightened out has been after someone 'replaced' half the parts on the car.

These kind of jobs will sucker you in with their assurance they have replaced 'this that or the other'.

If you want to fix it, start on it as if NOTHING has been replaced and go from there, satisfying yourself that each part and system is working properly before moving on the the next part/system.

If the guy that replaced the parts doesn't like that approach, the best thing for you and him is to let him find another troubleshooter.

Good advice for another reason. I had a motor home quit on the road. After much agony, I diagnosed a bad ignition module. I got a ride into the nearest town, got a new one and installed it. It still didn't run. So, I bit the bullet, had it towed in and waited until the mechanic could look at it next morning. Of course, the new ignition module was bad... (He was nice enough to get the auto parts store to give me a refund on the bad one...)

Jerry