Coolant System Malfunction - temperature guage not working

[Rd070707]

Hi all, I'm new to the forum, have a 2015 V40 RDesign Lux D4 Vea.

I bought the car with this fault "coolant system Malfunction, service required". I replaced the coolant temperature sensor about 5 months ago with a genuine Volvo replacement, and it didn't fix it immediately, but after about 2-3 days it just began to work, and continued for about 3 months.

Fast forward to now, I'm back having no coolant temperature reading on the dash most of the time, although sometimes when you start the car the reading shows for about 5 seconds and then goes back down to the bottom.

I had it plugged into VIDA and I got 2 codes for intake air temperature sensor (which I have now cleaned as it was caked in soot), one code for coolant temperature sensor, 2 codes related to invalid data received from ECM/PCM and one code for software incompatibility with ECM/PCM.

I'm struggling to know what to do next with it, I can't understand the reason why it shows a reading at times or 5 seconds on start up then it goes away again.

Any help greatly appreciated

[Rd070707]

I should have added that the fans run all the time, and the car and heaters does generate good heat

[Rd070707]

Anybody?

[Rd070707]

I have attached a screenshot of codes I have on VIDA.

When codes were cleared the temperature gauge did work again temporarily but stopped again the next morning.

I am now thinking of a few possible issues:

1- battery was replaced before we got the car. Could it have been done incorrectly? Does it need calibrated or anything?

2- intake air temperature sensor. Is it part of the MAF or MAP on these? Would be happy to try a known good sensor from another car to troubleshoot and see if it helps

3- ECM water damage? Is this common in these? Final step may end up being to remove ECM and inspect

Thanks in advance if anyone has any insight