unknown driver passlock problem

last night after work my gf and i went to the store she accidentaly left the aftermarket seat heater pluged in. when we got back to the truck the key fob wouldnt unlock the door, and when i used the key no power was on inside. no domelight, no dinging, the ip didnt even light up when i tried to start it. i figured the cold and parastatick drain killed the battery while we were in the store. i got someone to jump us and the truck would start then die imediatly, and the DIC would display unknown driver. i tryed "the door trick"(cycle key in door lock) as the tow truck driver put it. i tryed disconecting the battery. i even tryed the key relearn. nothing worked. i had it towed home and missed work to try and diagnose it. when it got home i unhooked the negative battery cable and let it sit overnight. when i got up in the morning i hooked the battery back up and she fired right up. i even cycled the key a few times to make sure. then went for a short drive around the block, noticing that my aftermarket head unit was not powering up and my bluetooth obd reader couldnt conect to the ecm. i figured it was a fuse so i popped the hood to check things out and went to grab my plyers from the cab and the unknown driver message was back. i had not pulled a fuse at this point. so i shut it of and turned it back on, fired right up but still unknown driver. then i disconected the battery adn pulled ever fuse i could find and methodicaly checked each one. then put it all back together and she worked fine again for a few minutes, then the message popped up againt but it acted different. i shut it off and turned to run DIC displayed driver 2. start truck and it says unknown. i pulled the ip and let it clear and plugged it back in, same thing. then my dad called and he sugested putting the stock radio back in, so i did and she started fine and the radio and obd port worked fine, so i assumed it was my adapter for the new radio and went back inside to take a nap. later i went out to start the truck to pick up my gf and the same thing as last night. i unplugged the battery again and left it sit so i could take her car to pick her up and now its too dark to mess with. wtf happened? did someone try to break into my truck? bad ignition switch? what should i check next? and how? i am out of ideas and short on money right now. any help is greatly appreciated.

First off, when you jumped your truck were both vehicles running? The manual will tell you when jumping to insure the jumping vehicle is not running when you attempt to start as it can cause a spike in your electrical system.

Also, how did you check your fuses? Be aware that if you are just looking at your fuses they can still be blown and you just don't see it. You really need to use a continuity checker on the fuse blades to insure it is good. (You can use a small light tester and a piece of wire if you need to. Light to one side of the fuse and the other side has the wire going to the positive terminal of the battery.

It likely is one of the ignition fuses. I believe there are ignition fuses under the hood and in the left side panel.

Could be a loose battery cable that cropped up coincidentally or a bad battery as well.

Rodney

Battery connections were bad. Negative terminal was stripped to the point that I don't know how it started at all. It started fine after the new battery was installed but an hour after a shut it off the problem was back.

Things I noticed but haven't checked Yet.
Obd adapter has always been plugged in when problem occurred.
Always occurred after failed attempt to unlock with fob.

so i re synced the key fob and my dad helped me re do the relearn for the passlock sensor. she started just fine every time today. I'm still going keep an eye on it but i can at least drive it to work.

for future reference to others if the problem happens. first try the passlock relearn(assuming good battery and fuses) go ahead and re sync the key fob while you are at it. if it still happens leave the ignition on(or whatever the problem happens with) and start pulling module fuses starting with the least important until the problem goes away. that module has then 1 gone bad or 2 has a wiring short to another databus wire or ground. if you get to ecm or ignition fuses(that powers multiple systems) the problem is likely the ignition switch/passlock resistor. there is a simple bypass for the passlock that fixes that problem almost permanently assuming you don't have bad wiring to the passlock system/bcm.

i did not get to try the fuses part since the passlock relearn worked after the battery install. i have suspicions that my pdm is bad or has bad wiring but it hasn't acted up for me to try. my plan is to if the problem reoccurs to first check pulling the pdm fuse(and many more just to be sure) and then if it still experiences the problem i will get the stuff to bypass the passlock.

here is the passlock bypass that we found. my dad used it on my little brothers Pontiac grand am and says it works just fine.
http://www.bergerweb.net/PasslockFix/

wish me luck that it doesn't mess up again.

OK so i did end up having problems again. almost exactly a week later. i pulled the bcm and tested the continuity to the wiring for the passlock sensor. it checked out fine. problem still existed after this. i then decided to try the bypass. it also didn't work. i disconnected the negative battery cable while i worked with the bcm. i pulled the aftermarket head unit and sent it and the adapter back to amazon and reinstalled the stock radio. the problem was still going on that night. the next day she was fine so i took her to a local shop that ran the bcm codes(for free luckily). the shop said it pulled every low voltage code in the book, and they suggested a new battery. i told them it was a new battery but the problem did seem to go away after i re hooked the battery. they said to bring it back by if the problem crops back up. so when i got home i took off both battery cables both of which were somewhat loose. then i cut all the rubber off the back of them and re torqued them to the battery as tight as i felt comfortable with. i wanted to wait a bit before i posted again to make sure the problem stayed away, and it has so far (knock on wood). no later than tax check time I'm going to at least replace the connectors for the battery terminals, if not the whole wire and maybe ill do a dual battery set up too who knows.

oddly enough the whole time i was having the passlock problem another problem that has periodically cropped up was fine and now that its fixed this problem is back. the problem is that my right brake light is out. the bulb is new, looks new, and works in a different socket just fine. OK i figure socket is bad, or a fuse some where, either way no voltage was getting to the bulb. so get out multimeter to test. it has voltage with the light not in socket, but as soon as you put a bulb in the socket the voltage goes away. almost as if its tripping a circuit breaker somewhere, but i didn't see one in the fuse panel. the truck did this once before when i first got it, it worked on purchase then went out. at that time i found a cut wire, that had obviously been cut for a while, near the junction block on the rrquaterpanel. i fixed the break and it worked for about a month then it happened again, and my dad and i messed with the break switch for hours until it finally started working. the next time it happened the bulb had a bad contact. now this time its a bit too cold to be crawling around under it guessing at what to check. any ideas? as I'm kinda stumped. my reverse light on that side is also out this time but i think that's unrelated as they haven't worked since i got it and only the left started working recently(decemberish)