These units are also notorious for having a scrambled CDF file in it after a battery replacement. If you can connect to the unit and check under the truck information you can look to see what kind of engine. 9 times out of 10 it will say it has a diesel in it not a LP if that is the case. Normally when this happens the unit will start and run but will not accelerate due to a speed sensor code. It is worth a shot just to see what happens.