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5 Posts
Discussion Starter #1
Well this is going to be an epic first post.. Needing some help with getting the car running again.

Information on car: 2004 LS 3.8L , Had and aftermarket remote start kit on it, Recently removed and all wires have been reconnected as it would be stock. Fairly low miles 80,000, Does have aftermarket head unit.

The what happened: Just like many of the other stories on this issue went to store in AM drove fine to and from let car sit about 3 hours got in car to wash it car doesn't start and security light comes on for first time ever since owning the car.
The car does turn over fine and sounds like it wants to run but just cant.

The strange out of the normal things I've noticed:
  • When putting the key in the ignition the lights for the Recirculation ,fresh air,A/C,defrost buttons flash briefly.
  • SECURITY light doesn't always get displayed when turning key from off to on, car doesn't start either way.
  • During the Relearn process SECURITY every once in awhile will Flash (I've read that when it Flashes it means the B.CM is in learning mode) 99% of the time it just scrolls like the other messages in display. If i just turn key to ON and not bump the motor over most of the time the Security will appear sometimes not. If I bump motor over 99% of time no security will be displayed.

The things I've tried to get car running:
  • Went to Junkyard= JY (I know not the best for troubleshooting, Hey gotta start somewhere) from a 2005 3.8 L picked up a complete ignition switch with key, B.C.M. ECM/ECU.
  • I had the car towed to shop to have all the Anti-theft functions disabled via HP Tuners software they did a complete rewrite when done changing the functions. No luck
  • I have tested the connections at the ignition switch for the proper voltage results are. Black =0 , White= 12V, Yellow= 5V.. all is good.
  • Made sure i had continuity from Switch to B.C.M good there as well. Also made sure i had voltage at the B.C.M and a good ground.
  • Cleaned ignition switch contacts. Didn't look bad at all to begin with
  • Checked all fuses in all fuse panels. Everything has power nothing blown
  • Blower motor, lights Instrument cluster etc all still working fine. Car just wont start
  • Fuel pump does run when key is turned to ON. Have notice fuel smell when cranking sometimes.
The following I did the 30 min relearn every time i change a part.
  • Installed JY ignition switch with original B.C.M/ECU
  • Installed JY BCM, Ignition Switch with Original ECU
  • Installed all JY parts above. No original parts in car
  • Tried an extra Instrument cluster with all JY parts just in hopes as i heard it could be an issue.
Only thing left I can try is wire in the 2.2 resistor in the switch. Actually just waiting for them to get delivered. If the Resistor doesn't work hopefully a new Ignition switch will fix the issue.

If anyone has any more places I could look into please let me know. I have put a good amount of money into the car since getting it and would not want to scrap it as the car drives good and is/was reliable, easy to work on up to this point.

6 Posts
I have a 2002 LS 3.8L with basically the same problem. This car sat for around 5 years with a dead battery. Got a new battery and did the relearn and then it started. I changed the oil and haven't gotten it to start since. Changed the ignition switch because I had NO power. Didn't help. I disconnected reconnected the black battery cable. That would reset something and I would have power but when I turned to key to crank all power would shut off again. I determined that if I unplugged the 3 wire anti-theft harness from the ignition it would not start but at least I wouldn't lose all power. Got the 2200 ohm resistor, wired it up, did the 30 min relearn process and on the moment of truth crank, battery died.

Still working on it but allegedly you can get a new BCM from or preprogrammed to your VIN for waaay less than a dealer or parts store. I have not used either one and can't vouch but I see myself using one or the other of them in the future.

The other thing is, my car is Passlock 3, with a transponder in the key that supposedly does an RFID kind of thing so I'm not sure why the resistor trick would be beneficial. Do transponders go bad? Do we just need new keys and a relearn?
If I figure it out I'll post here.
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