[ReaperF30]

I've got the codes P0597 (thermostat heater control system open circuit) and P00B4 (Radiator coolant temperature sensor circuit high) does anyone know what these mean and the location for the Radiator coolant temperature sensor ?

[Billfitz]

Look them up at https://bmwfault.codes/ and realoem.com

[MidMoF30]

P0597 is for the t-stat. I would assume that if you're getting the P00B4 code you're temperature sensor could have failled too.

Do you have any issues with the coolant temperature read out or weird values?

If the t-stat is stuck open, I would assume that the engine will take longer to come to temperature, but not overheat.

Nonetheless, its worth replacing both. I happen to have the P0597 and will be replacing the thermostat, pump, and flange all at once (Kit from FCP Euro).

[ReaperF30]

Originally Posted by MidMoF30

P0597 is for the t-stat. I would assume that if you're getting the P00B4 code you're temperature sensor could have failled too.

Do you have any issues with the coolant temperature read out or weird values?

If the t-stat is stuck open, I would assume that the engine will take longer to come to temperature, but not overheat.

Nonetheless, its worth replacing both. I happen to have the P0597 and will be replacing the thermostat, pump, and flange all at once (Kit from FCP Euro).

Car takes like 10ish minutes to warm up but it's winter so I thought that's normal, and I wanna replace the Radiator coolant temp sensor to see if that fixes the problem before the thermostat, but I just can't seem to find where the sensor is

[sspade]

Very common failure and covered under extended factory warranty. Head to your nearest BMW service center for replacement. Should cost zero dollars.

-former N26 owner who did exactly as described.