Transmission codes

Post by **misha** » 15 Nov 2022, 15:17

Doesn't matter as long as it's correct for your car.
Usually the "T" number is matching with production year of a car.

This picture is from a parts car...'96 2.5 20v:

: IMG_20201116_135020.jpg (261.38 KiB) Viewed 314 times

xanthefin · Post by **xanthefin** » 16 Nov 2022, 19:37

Good call.
If you dont mind i would want add link to this topic in there if detected this fault code and it doesn't make sense after checks..?

Post by **hausmeister** » 05 May 2023, 00:10

Hey, I have been driving the car more now, and noticed something odd to me. The fuel consumption has gone up quite a bit (~1.5L more or 2mpg less), and I do not notice the lock-up clutch engaging any more. before I could definitely tell it was going on/off, probably somewhat similar to the non-turbo table.

Do I understand this table correctly, that in my turbo it will only lock up past 129mph? Which would be 207kmh - much more than we are allowed to drive here. So it will never engage for me if it is working correctly, and it did not work right before I replaced the TCU...?

: lockup-table.jpg (74.08 KiB) Viewed 265 times

Post by **abscate** » 05 May 2023, 05:39

I suspect those numbers are kph, not mph as labeled

Post by **hausmeister** » 05 May 2023, 06:55

abscate wrote: ↑05 May 2023, 05:39 I suspect those numbers are kph, not mph as labeled

That would make much more sense, I can definitely check for that. In any case, it seems for some reason the previously faulty TCU activated the lockout more like the na - at least for 4th gear I am sure it did it. Partnumber is the same as the replacement... strange.

Maybe installing an n/a TCU would be a fuel economy hack?

(goodbye clutch)

Post by **abscate** » 06 May 2023, 01:34

misha wrote: ↑15 Nov 2022, 15:17 Doesn't matter as long as it's correct for your car.
Usually the "T" number is matching with production year of a car.

This picture is from a parts car...'96 2.5 20v:
IMG_20201116_135020.jpg

Misha, thanks for that note on the date code. I was looking in parts the other day and had a 1998 and a 1999 TCU and was wondering how to tell them apart, now I know!

Post by **scot850** » 06 May 2023, 11:02

The lock up is around around 90 kph? Not sure what those numbers are?? Now I recall testing for this with a Volvo shop foreman years ago, but now can't recall if it was a 4-speed or my R with the 5 speed auto. It was done in the city so almost all the streets are under 80kph speed limits.

More research required by me!

Neil.

Post by **hausmeister** » 07 May 2023, 12:59

I was just wondering, because my previous bad tcu did engage lockup around 80-100kmh. Probably also a malfunction if it is not supposed to do it on 2.3turbo cars.

Edit: Fuel consumption is down again after ecu reset. I should not be lazy and swap ecu without removing batter power.

Post by **FireFox31** » 09 May 2023, 13:15

This table is interesting. My 2000 V70 NA with bad transmission fluid had a weird power drop out at 44 mph. When I asked the forum, they suspected the torque converter have a lock/unlock problem. My problem at 44 mph matches the 3rd gear "lock up off" speed. However, my 2000 V70 is a 5-speed auto. Still interesting and I'd like to learn more about this system.

Transmission codes

Re: Transmission codes