i have recently bought a 3.0 trooper , and noticed that thier have been some changes to it, i first noticed that it was not going into 4wd as the light just flashes and i'm unable to move the l/h ratio gear stick , i then noticed that the heater plug light dosn't illumiate, so on further inspection i found that the engine has been replaced with the better 3.1 and thier is a button that has been installed you have to press to get the heater plugs to heat up. i know that this is the better engine but should i be able to get the 4wd system to work, or does it need some tinkering, i have noticed that the relay box , if you look from the front of the car ie driver on left pass on right , in the top right hand side it looks as though thier should be a relay box as thier are some wires etc that are not attached to anything. can you help or can you recommend any one who knows how to get the 4wd system to work ie a specialist, many thanks