1998 S70 :TCU replaced but do I need Vida to connect?

Swedishcar · Post by **Swedishcar** » 24 Nov 2025, 14:27

The orange up arrow and CE light are on and shifting is bizarre but it drives.. I bought a $25. TCU module and replaced old one but now I apparently need Vida software to connect it to car. $380. at dealer; nobody else seems to have it and I don’t run Windows anyway. ( minimal computer use and I use Chrome).
I really hate this car! Give me back my old 240 or 745 any day. Now I have to find the code to radio as I disconnected the battery to install TCU, as prompted by online safety advice…
So, bottom line: how can I get the car to recognize the new TCU and how much damage am I doing by driving it with the weird shifting? At least the transmission fluid looks ok. And do I have to pull the radio out to find the serial number to get code?Old Volvo plastic has a way of breaking on me, being the novice mechanic that I am.
Any suggestions much appreciated!

Post by **misha** » 25 Nov 2025, 01:19

On '98 & prior you don't.
'99 and later yes since they use CAN network.

Swedishcar · Post by **Swedishcar** » 25 Nov 2025, 10:52

Thank you for your answer! I installed the module, but I must need to do something else as it hasn’t changed the car’s performance. Can you advise?

Post by **misha** » 25 Nov 2025, 12:41

When there are fault codes stored in TCM module,they don't reset with battery disconnect like engine ecu.
You will need at least VOL-FCR or 850app to read & clear the codes to see what's going on.

Why did you replaced TCM at first place?

Does the orange arrow flashing or it just stays on?

When TCM store a code(s) you don't replace TCM...you read the codes to see what and where is the problem.

To me....it looks like the replaced TCM stored the same problem like original TCM...so problem is in auto transmission or some of it's components.