[racertim]

It was suggested that I post in the s60 forum since drive trains are the same as my XC90. Here is my post: I have a 2006 XC90 fwd 2.5t with 150K. Long story needed to have engine replaced. Local mechanic shop (son-in-law but that's another long story) replaced engine with a good used one. Took him forever to get it done so car sat for months at a time. Finally done, engine runs great BUT when you shift it into Drive, it will go forward and shift through the gears. When you come to a stop and want to put it into reverse it will not go into reverse. If you disconnect the battery and then reconnect it, it will then shift into reverse. Same story going back into drive. You have to disconnect the battery and reconnect and then it will shift into drive. So he takes it to local AMCO shop to look at it. All they can say is that the transmission needs rebuilt. The transmission worked flawlessly before the engine was replaced. I am thinking so did they not hook up a wire correctly or what? I find it hard to believe that it was working great before the change out and now it just isn't. I called the local European Motors shop and they said $3000 to replace the transmission with a used transmission. But I am not convinced that is the issue. Does anyone have any advice on how to diagnose what might be happening? The car is in great cosmetic shape, but need to get the mechanical stuff right!
Thanks!

 

[chefricky]

The first thing I would check is the PNP switch for alignment.It could also be a failed switch.Linkage maybe too? It figures that Amco would tell ya that ya need a tranny.

 

[Eric T Johnson]

Welcome to the world of cars equipped with computers and related electronic controls. For your sake, I hope the problem is fixed by realigning the PNP switch. If you can temporarily fix the problem by disconnecting the battery, and reconnecting same, then you are not dealing with a mechanical defect in the transmission. Your description sounds exactly like a failure in an electronic control. Perhaps a memory was corrupted. Perhaps an overvoltage destroyed an electronic component. Perhaps a multi-pin connector is not working as it should. Cheer up! You could be sitting on an airliner that is pointing down at mother earth, controlled by a wayward computer. Count your blessings!