2003 yukon xl passlock problem

Hello. Please help. Have a 2003 GMC Yukon XL with a no-start security issue. Anyone's experience with this? Here's what I know, and done thus far. Passlock on my vehicle has four components: lock cylinder, passlock module, BCM, and PCM. No "chipped key" (key cylinder itself sends resisted voltage to the BCM). The BCM sends a 12v reference to the Passlock module, module sends a 5v signal BACK to the BCM (with an added resistance), creating a vehicle specific voltage level (somewhere around 3.5v, I assume). The BCM then sends a "flow" or "no-flow" signal to the PCM, telling the injection system what to do, based on whether it perceives that value is correct, or constant. My Yukon cranks, turns over, then immediately dies. The "tell-tale" security dash light is on. Sometimes it's constant. Sometimes on for 5 sec. then off. Tried and retried the security "relearn" feature a million times. Doesn't work. I'm assuming because there's no consistent resistance to "relearn". In the 30 minute procedure, after each 10 minute cycle, the security light never goes off. Constantly stays lit. Pulled the PCM and had the VATS command "flashed" out of it. Figured I just start with the main issue: getting fuel flowing at the injectors. Didn't work. Still no start. Don't know if the programmer (guy who did it) had the right software or not. Used C.A.T.S. Flash cost $100. Been undriveable for two weeks now. Metered the Passlock Sensor, it correctly sends and transmits the 12 and 5v signals, but I don't know the supposed "vehicle-specific" reference voltage sent back to the BCM. I really hate to go back to the "see-if-electrical-components-are-properly-shaking-hands" method, but my PCM foul has got me gun-shy now with that fix. Pulled and re-pulled fuses so many times, don't know if they'll stay seated anymore.   (joke)    :D Going to recheck now again though, because of reading the thread where the guy's injection fuse was the culprit. Wasn't completely burnt, just had a hair-line fracture. Any info anyone has would be great. Or if you can redirect me to an already-posted thread..

Here is a link to some interesting info on bypassing the Passlock2 system, all for the price of a !/8 watt resistor :

https://www.the12volt.com/installbay/forum_posts.asp?tid=123309&KW=racing%5Fbidule

If that is your problem, it will fix it.

Soldering is fun!

My experience with passlock 2 is if it's a resistance issue the vehicle will not crank at all and the security light will stay on solid. Leave the key on for 15-20 minutes until security light shuts off, turn ignition to off, turn ignition on and wait for security light to shut off again and then start the vehicle...I uploaded the DEI wiring information if you want to test.. https://www.the12volt.com/installbay/downloads.asp?srch=all&term=1048