1999 Volvo V70XC No Reverse

[chrafael]

First thing I'd do is download an ATSG manual for the AW50-42le trans. Then follow the guides for diagnosing the electrical system and do the pressure test. Anything else is guessing. If the trans isn't coding, and the solenoids ohm correctly then it probably isn't them. The solenoids could be clogged but you won't know without removing them. The reverse lights have nothing to do with it. Low pump pressure causes a lot of problems that aren't obvious. I made a gauge out of some 1/8" tubing, an old R-12 dial and a universal adapter kit from the auto store (Dorman or Help! I think). More things happen when reverse is selected than the other gears so failure shows up there first. Could be self preservation. Both solenoids on locks out reverse over a certain speed. BTW, don't throw away your original valve body as running changes were made through the years. They might interchange, might not. Lastly, don't go into the valve body or trans unless you are really committed.

[drosser]

So- I finally had some more time to play around with this (had some other projects). With VIDA/DICE in the Vehicle Communication tab, under TCM, you can manipulate each solenoid and Vida will tell you it's status. With the car in Park, I can turn on and off each solenoid and the status will change. When I put the car in R, S2 is on. I cannot turn it off. In fact the thinking wheel keeps spinning.

Questions: Does the fact that in park I can manipulate the solenoids indicate that they are ok (plus the fact that the car drives normally in all other gears? What would prevent the TCM from being able to control this solenoid in reverse but allow it to switch them on and off in other gears? Thanks for your time.