zlacker

If you just buy a bare sensor, yes, it's going to be +/-5. They also have a non-linear response which needs to be dealt with as well.

If you are only concerned about a 20 or so degree temperature range it's not an issue, but if you are trying to read over a 100 degree range, you'll want to account for non-linearity as well.

Also, accurate and precise to 10ths of a degree isn't really attainable unless you do fancy math as the sensor will heat each time you read it. The idea is to take multiple readings and average them but unless you are accounting for the heating of the sensor, your numbers will be garbage.

This is for consumer grade sub $50 sensors. Of course you can go fancier but you have to pay for it.

>>throwa+(OP)
This isn't something I know anything about, but I know that 1-Wire exists and so on so am able to locate something like https://www.analog.com/en/products/max30207.html pretty easily. $2 in quantity, reports a temperature digitally, accurate to 0.3 C between 0 and 70 C.

What is it about that device (or similar) that would put it out of scope?

>>throwa+(OP)
It's probably not that the sensor is bad. It's the location of the sensor that is tucked away in the interior foam so that it's not reading the air inside the cabin