Hi,
I've had my 2001 1.9T for almost 3 years now. Ever since I've owned it, the transmission would occasionally slip. It would do it maybe once a month at the time, so I did not think much of it (thought it was likely not mechanical but something with the electronic transmission control). My mechanic told me not to worry too since I have an extended warranty (great I said!). As of lately though, this slip has been occurring on a more than weekly basis. The slip is very smooth and there is no grinding noise or clunk at all.... it's just like the transmission falls into neutral for a split second and everything is back to normal. It usually happens on light to medium acceleration. I had the dealer check it out and of course it did not happen on the test drives. So they ran a diagnostic and found and error code (TCM-29) when trying to update the transmission’s software. They told me I need a new Transmission Control Module (part# 30644070) as per a Volvo service bulletin. Has anyone had any experiences with electronic versus mechanical transmission issues and know if this makes sense, or is it a mechanical fault?
Thanks, in advance

Though not versed in the mechanics/electronics of this transmission, I too have a V40 and am experiencing a similar issue. I've intentionally neglected to have it repaired, as other issues with the car are taking precedence. However, I'd love to hear from you about your decision to repair or not to repair, and what the cost is if you do. Thanks!
--Allen

Hey there Allen,
Just to let you know that it was not the TCM in my case ... although someone at volvofurms told me he has the same problem and that it was resolved by a new TCM. I'm not sure what to do at this point, but am open :) Will keep you posted as soon as I have news.
Regards,
Anthony

Looks like everything was checked but how about the fluid level and when was the last time it was changed?

Although this is listed as a "Lifetime Fill", that is pure BS. Any fluid is going to wear out over time - no avoiding that.

Have the fluid replaced with the proper spec fluid JWS3309. The dealer wants too much for the stuff so do a search for AVLubes. They sell the proper stuff for about 50 bucks a case. You can flush the fluid yourself by going to S40concepts.net and searching their how-to section for the procedure. A guy there did an excellent write-up with pics. Also has a link to the AVLubes site.

I would lay money that this will resolve it.

Good luck,
mormit
--
02 S40 now my daily! :), 98 V70 T5 new wife mobile-very nice!, 85 245DL 275,000mi V15cam It takes a licking and keeps on ticking

Hey there Mormit,
Thanks for the advice. I had the fluid changed after i noticed the problem the first time (about 90k km). Had it done at my local Volvo garage (they do Volvo and Saabs). The fliud was pretty dark according to the tech (i did not see it). I'll have this done again and be there this time... i am on vacation now far far away :) I'm at about 112k now and will be beyond 114k when i get back.
Will keep you posted!
Anthony

they are correct. the tcm cannot be upgraded anymore because it is a hardware problem as well. you replace the tcm and run an adaption proceedure to ensure proper shifting.

Hey there,
Thanks for the info ... Just to let you know that I did have the TCM replaced under extended warranty (with new software), but the problem is still there. Is there additional software to be downloaded, or am i dealing with a problem with the actual transmission? There is still no gear grinding ... this is why I have my doubts about a mechanical fault.
Thanks for any advice you can offer!
Anthony