@Mustapha Than take a look at the manual which can be found here https://www.volvocars.com/fr/support/car/v50/10w46/

If you just want to change the language, you just need the adapter I posted, and a charger. No time consuming pin cracking required. If you are lucky, it is even possible for free, but usually it will cost a small fee.
And don't even think about programming your car without a charger attached. The V50 is really sensitive to undervoltage and will turn into a giant paper weight, when the battery voltage is getting too low.

@Mustapha You won't need to decode the CEM, if you just want to change the language in the dash and radio. This can be done by Vdash without cracking. Simply connect the car, click on the language menu in the top right corner and follow the instructions. You might want to look here https://d5t5.com/partners for a vdash partner near you, that can do this for you.

@Mustapha Try to turn the volume control in the center console, while your hear them beeping. The one for the radio.

@Mustapha You need to attach a charger to the battery while decoding the CEM and also while coding/programming the car. The charger needs to be able to maintain a constant load of 8-10 Ampere for hours. This means you need a charger with at least twice the peak power (16-20A) of that. I'm using a CTEK PRO25S for example. Stay away from noname brands.

@Doc https://svdns.info/2024/01/20/key-coding-p1p2p3-spa-cma/

After doing some research in VIDA, I found out that this car doesn't seem to have a SCU. Instead everything related to the IMMO/starting the engine is handled by the KVM. This would mean no coding possible with Vdash unless you have the KVM pin which can't be cracked by Vdash. VIDA states an IAU reload is needed after changing the IAU. Start button and iginition switch don't need any software after replacement.

@Mustapha the software https://d5t5.com/sw/vdash.exe
The adapter https://d5t5.com/eshop/detail/180/super-j2534-volvo-dice-9513000-replacement
You will also need a powerfull charger and lots of patience as you first have to crack the CEM pin, which can take up to 24 hours, sometimes even up to 180 hours.
On what car do you want to change the language?

@pamie849 The switch you ordered is just that. A dumb switch and a part of the SCU. The programable part is the one I have posted above (31252952). The whole SCU looks like that according to EWD
Continuity doesn't mean there is actually communication between the ecus. You would need an oscilloscope to check that.

What error 1215 means is beyond me. You will need to ask the guys from D5T5 about that.

@pamie849 The SCU is nr. 1 in this diagram. https://volvoparts.barrybourke.com.au/a/Volvo_2015_V40-25l-5-cylinder-Turbo/_51513_12294337/Ignition-switch/GR-367012.html

What exact DTCs do you have, and did you check all fuses?

@zgr444 Enter your VIN in the search field on the D5T5 homepage. All tuning options possible for your car should be shown. But as your car is polestar tuned, you should try to contact Obbe tuning, who is making all tunes for Vdash, first. The "Original + EGR off + DPF off" tunes are usually based on the non polestar software and would remove the polestar tune from your car. At least for the engine. I have no idea how the transmission part of the polestar tune is affected.
If you have a working Vdash setup, you can also just connect your car and click the engine optimization option to see all options possible. This should check the software version of your ECM, and present tunes based on that.
To tune your car, you will have to crack the ECM pin, and maybe also the CEM pin first. And you will have permanent DTCs afterwards, that will clearly indicate that your car runs with modified software. And if you have to visit a volvo dealer or want to do an OTA update, you will have to revert the car to the original software or the car will be blacklisted/blocked for all software updates/reloads.

I'm somewhat clueless to be true. Could you post all codes that are present in your car, or a screenshot of them? Active and temporary.
The main problem is, that you already started to fire the parts canon and swapped in used parts, that could have brought additional problems with them or they are simply the wrong part, as Volvo changed some things around the transmission over time. There are different part numbers for the transmission, valvebody and so on, depending on the chassis number, if look them up in VIDA. There are also at least 5 different software numbers for TCM that I found so far. Trying to help you is like looking through a crystal ball. More or less just wild guessing. Maybe you need to visit a local Volvo specialist.

@Prinz-Bernhard complete hardware change needed.
Here is little lecture about it. https://svdns.info/2023/08/27/so-youve-bought-an-import-volvo/

Greatings from the south of Berlin.

@DahuNejc the main focus of Vdash is coding, not service and diagnostics. Some functions are just not implemented (jet), or are located where you don't expect them. Lots of functions have to be started from the CEM for example.
You might also want to take a look at this program https://vtool.info/ which is made with diagnostic and service as main focus.
There is also a mobile phone app called V-Tool https://v-tool.app/ which should have the roof calibration function.

@bochenn No problem. That's what this forum is for.

For your first steps with Vdash follow this :
Install the Super J2534 drivers from here https://d5t5.com/eshop/sw/J2534_Driver_x64.msi
Then connect the adapter to the OBD port first, and after that to the computer. Than turn the ignition to pos. II (ignition on, engine not running) by pressing the start/stop button for maybe 3-5 seconds, but without your foot on the brake pedal. Than start Vdash. Log in to your account and press connect in the top left corner.
You should see all modules that are installed in your car after that.
Don't buy any subscription or configuration changes until you haven't cracked your CEM pin.
And no tunes until your ECM pin isn't cracked.
If you have any questions, just ask.

@Caerbannog13 R6 seems to be only present at the 1.6D. The starting is completely controled by the ECM once you turned the key, according to VIDA. There are several dependencies how and if this functions operates. Outside temperature, clutch switch, brake switch, battery voltage and so on. If you have VIDA, you might find informations why the autostart failed under Diagnostic/Vehicle communication/CEM/Advanced.
How old is your battery?

@Ctrl-alt-delete https://volvoparts.barrybourke.com.au/a/Volvo_2018_XC60-20l-4-cylinder-Turbo-Diesel/_51507_12286919/Compressor-exhaust/GR-466266.html
Should be nr. 33-37 in the diagram. There are several videos on youtube. Just search XC60 EMAP pipe.

@Caerbannog13 better resolution

@bochenn By the look of your windscreen, I would say your car has the City Safety sensor, collision warning sensor and rain sensor, but no FSM.

@Caerbannog13 R6 part number 9441161 or 30765030 depending on the chassis number.
R13 part number 9441160 or 30765032 also depending on the chassis number.
If your VIN ends with a number below -270000 it's the first number. 270000 and higher, the second number.

@Caerbannog13 check R6 and R13. Also check the clutch switch, if your car is a manual.