Help with codes

I have a 1999 alero with the 3.4L. I’m having trouble with what is acting like the Passlock but my security light is not on and I have not replaced any parts. 2 weeks ago the car just shut down while driving trying to restart it would run at 400 rpm then die. after playing with the key and trailering it home I put my solus scanner on it and found that the U1000 had tripped and knew that passlock was tripped I was able to reset it and had no problems until Monday during the first heavy snow in MN. After trailering it back I found several codes and again U1000 the vehicle will start after all codes have been cleared but as soon as you press the gas she dies but no security light at all. Sure seems like passlock but I’ve tried to clear it and getting nowhere. Here are the codes that are coming back after I clear them and try to restart

B3267
B1374
B2752 Horn Relay Circuit Low
B2808
B2965
U1040 Loss of EBCM / EBTCM Com
U1096 Loss of IPC Com
U1000 Loss of Class 2 Serial Com
P0463
P1610
P1641
U1255
The car just died like it ran out of gas. (Half tank) it dose start and run for a moment at 1000 rpm but press gas and it kills. No security light on and run thru passlock procedure and nothing helps.
Please guys any help would be great. I am a Bodyman by trade and am out of my element.

Unfortunately, you really need schematics, a manual, and a high level scanner to read data for all these problems....especially the communication codes....

More often than not, a communication code is set by loss of power, loss of ground, loss of signal(due to short or open), or a bad module.....just too many possibilities here.....

About the only thing you can due is check fuses for open, and make a visual of all wire harnesses for a possible rub though condition......

This can be a wild goose chase if you don't bring it to a shop or dealership, and their best electrical guy doesn't get it....could find a wiring problem right away if he's good, or this could turn into an electrical search, especially if they don't know what they are doing.....

The other possibility is after market equiptment that is added to the car and might be causing aharness problem.....