This is a simple question, but I could not an answer by searching the BB forum.
I have a 2001 V70 which has all known transmission problems - hard shifts, 'Transmission service required", CEL light, once in a while goes to limp-home mode.
I want to try another TCU before going for transmission itself. They are cheap used, easy to swap.
My question is - if I find the exact part number and version number, can I swap it myself or it will not work unless dealer 'enables' it??

Thank you

Before you swap TCUs, which can probably be done, I would check the service work performed. There are software upgrades which need to be done to get the tranny to operate smoothly.

Find out what the tranny codes are by borrowing a scanner at your local autoparts store. Any balking solenoids can be replaced fairly easily.

Have you flushed the tranny fluid, 3309 for 5 speed autos? Is it brown or very dark red, does it smell burned?

If you get a used TCU, you will still need to get updates at the dealer.

Klaus
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Praying for Cynthia Amendt, heaven bound

I went to a dealer, they said everything was up to date. I did not have codes then.
The car is comfortable and fits my needs perfectly, but it drives like POS, worse than any car I had to date (and I had 3 Oldsmobiles). Just awful.

Ok, so I vented a bit.

The fluid has never been flushed (81K now), it does not smell burnt, and the color is adequate for this mileage. I flushed transmissions before and concluded that it is a waste of time and money. I do not doubt that fresh fluid is alwasy good, but the problems I have now are way too severe to be fixed by fresh fluid.

I wanted to try another TCU, since I still have some miles left on my aftermarket extended warranty, and they said that before they consider paying for transmission they want to make sure this is not TCU (which they do not cover).

Also, there are technical bulletins from Volvo around this time (2001) that describe my exact symptoms and they state that this is consistent with the TCU "failure to adapt". If for some reason adaptation did not finish, the TCU would not know when to shift and would kick gears randomly, like my car does.

So, I can buy a used working TCU for under $100, swap it, and see if it helps.
But if the car will not run after I swap it, I would not try this at home.

So, did anyone swap a TCU? If yes, did teh car start and ran?

Yuri