ok here is the deal,
i have a 98 bonneville ssei. fully loaded with every button manageable....(its aggravating)
1- my security light stays on while i am driving.
2- my car will sometimes not start.
we have checked the following-
alternator
battery, terminal, and cables
starter, starter sleinoid
ignigtion, and keys
and all wires that connect all of this are working properly have been tested with volt meter.



when i try to start the car everything comes on. all my gages show up. you can hear the fuel pump start up, it will NOT try to turn over, and you will not hear any thing from the starter. now what do i do? i have thought about it being my grounds where all my vats, cpu, fuel pump and starter ground at. i have thought about my starter enable relay and tested it and it says its good. i dont kno wat else to try. and where the issue is coming from according to my wires i have power everywhere it should be but it just wont start.
HELP PLEASE!

Look at this thread https://www.gmforum.com/t278980/ and then check your ground bus and clean it.

You may be having a VATS issue, but you said that the Security light stays lite while driving it and then you say you can't start the car. So...not sure now. You can try by-passing the VATS https://www.gmforum.com/t279119/ and see if things improve.

ya like yesterday i got off work drove home and then went back out to my car like literally 5 min. later and it wouldnt start up. but that also happened about 3 days ago. and for the past 3 days since all this hapened my security light stays on. and when it did it yesterday , my security light is still on

as for the ground bus. i have already checked that, and it has no corrosion on it, wipe it clean and its fine. as for the vats, i have tested my key and it still works properly i am getting power from my key when i turn it forward and i have tested to ohms on my key it self and its fine.
the only other thing is....my car leaks when it rains. i dont know where from. but i kno that the water for the most part ends up where my ground bus is. i dont kno wat to do.....
help!!!

Check for holes in the body under the car. If water is splashing up it can corrode teh wires.

Try cleaning the key VATs real good. It may have a poor connection.

i thought about that and even if that was the case it really wouldnt matter, because it is a bunch of grounds...water would do nothing but help it conduct. and i have checked for corrosion and there is none. but here recently it has started to not start much more often than before, i believe what ever relay is messed up is going to be going out for good here soon, so then i can just retrace my voltage again and find out which one it is. hopefully. any other ideas????
also i have cleaned the key and still nothing helps. lately i have been able to get it started rather quickly when it dose this. the only thing i do is....turn the key forward to start and just keep turning it back and forth untill the (from what i can think electric signal) from the key that travels that path of wires is when i do that so many times in a row it finally lets that relay connect. like the relay is sitting there going "im try to connect im tryin im tryin ok finally" because finally you get enough volts through there quick enough that it makes the connection and stays.


any thoughts??? please help this is getting really aggervating....

Water isn't a good conductor of electricity unless it has metal solids in it - rust, salt, iron. However; if there is rusty water present, with our without noticeable corrosion, on a hot wire the wire can go to ground. If it'* a signal wire for a sender or relay, then the voltage will drop off and then the problem presents.

Chasing down electrical problems is time consuming and hair pulling.

If you have a sunroof, you're drain lines may have come undone or the drain line is plugged up. These will leak under your carpet and pool in areas behind the front seats.

thank you for that about the water. and where do i find those drains??? any ways about the leak and water. it only leaks when it rains really hard. but when it does my front floor board in front in of driver seat gets soaked. ya know right where that ground bus is. any ways i dry everything up, but i can never seem to get all the padding dry and it consistently stays wet for a good couple of days. normally when i go and remove the cover to it, its not normally wet i just do it because i have in my mind that it helps ya know. so i don't know but im sure it will dye soon enough, hopefully and i can just fix it. any other thoughts would definitely be appreciated if any one has any. thanks
hope i get it fixed, if i do i will let yall know.

If you find any holes try filling it with some expandable foam. But try to remove any rust you see. The get some truck bed liner, the kind you paint on and coat everything real good.

The security light staying on is probably the clue. That is a symptom of something not right in the VATS system--the antitheft system. It senses the resistance in the little black insert in your ignition key; if it is correct per the programming of the VATS module, then it will let you start. If not, it will not allow the starter relay to close.

This problem really sounds like your VATS system is intermittently sensing the wrong resistance in the key. This is usually due to worn contacts in the ignition switch. I have been through this twice in 260k miles. The first time, the dealer replaced the ignition switch. It worked, but after parts and labor it was the better part of $500.

The last time I'd had enough of those repair bills, so I found the wires under the dash left of the column that go to the VATS sensor in the ignition switch, and *cut them.* I soldered in some resistors such that it now always senses the correct resistance.

By the way, if your contacts in the switch are intermittent, the VATS system usually is programmed to not allow a start--even with the correct key resistance--for 5 min or so after an attempt where the wrong resistance is sensed.

Use a multi-meter and check the resistance of the pellet in your ignition key. Get a wiring diagram, and go under the dash left of the steering column. After you remove all the plastic covers, you can find the big rectangular connector that brings the steering column harness into the dash harness. Its held in with a bolt in its center. pull the bolt; get a wiring diagram for your car and identify the terminals for the two wires that go to the ignition switch VATS resistance sensor. Check the resistance between those two terminals with the key in the ignition. It should be the same as you measured on the key. If you get 0 (like I did), your VATS contacts in your ignition switch are likely the problem.

Then you get to either replace the ignition switch, or do what I did and solder in resistors to 'fake' the VATS system into thinking the proper key is present all the time.

The first solution preserves the anti-theft feature of your car. The second doesn't, but its a lot cheaper.

just one question, when your car did all this did it do it the same way mine has? like not wanting to start every so often? and all that and haveing checked all the things that i have checked, because i am thinking about going with the second solution because thats what i need rite now. oh and in any way possible will doing the second option set off my check engine light? because i am tired of lights being on and something being wrong right now lol.
because this is the only thing i have not done is by-pass my vats, and if its the only thing i havent tried its probly the thing that will solve it. because thats how it always works.