As per the title I know this is possible to do. What i want to know is that considering some of the Passlock system is in the BCM if tuned out of the PCM will it cause the BCM to not allow startup? I read on another forum a guy tuned out Passlock on his 99 silverado and it woudn't start. He unplugger the BCM and it started. Problem with unhooking the BCM is that when I pull the fuse the keyless entry stops working. Is getting rid of passlock as easy as tuning it out like on the earlier VATS cars or does this cause other problems? My passlock acts up all the time, just want to get rid of it.

 

Also when the security light comes on the fual gauges and temp gauge go out. Will tuning out the VATS system keep those gauges from working correctly as I assume they are tied to the security system?

I tried narrowing down how the gauges are wired but i'm not the greatest at reading a wiring diagram. Still trying ot figure this out.

 

Bump..

 

Ahhh, more information always helps! Fuel and oil pressure gauge going out when the security light comes on is very similar to a problem I encounted on a Blazer a while back. What I found, (with the help of a big magnifying glass) was the female connector on the cluster had several cold and loose solder connections to the circuit board. It required removing the cluster from the dash, and removing the printed circuit board from the cluster. The connector has 24 pins and each one was de-soldered and re-soldered using a low wattage, pencil type soldering iron and 60/40, (lead/tin) rosin core solder.

 

Well it seems to have the issue when the security system acts up. The security light stays on and the temp and fuel gauge go out. Security light goes off and the gauges come back on. Usually it works for quite awhile after unhooking the battery. Then it starts to act up again.

 

Have you checked the BCM for DTC's? It will require a scan tool capable of accessing the BCM. The check engine light will not come on when a DTC sets in the BCM. If the Passlock system has a problem, it will store a DTC. With the cluster lights messing up, the IPC may also have set a DTC.