[trebor]

Hi Kamil, I understand what you are trying to achieve and not sure how you have wired the ignition to switch off your remote but it looks like what is happening is that your remote is getting the signal to switch off before the supplementary mode is kicking in, which is enough to shut down the FBH and restart it again once it has completed its shut down procedure.

I assume you live in a cold climate but don’t forget that whilst the remote will switch the heater on at any time the supplementary feed needs the temp to be 5 degrees or below

The heaters are designed to use pins 1 and 3 ,one for supplementary and one for parking heater, so why not use as intended and remove whatever you have wired to the ignition ? You could always isolate the supplementary mode and just leave it working as a parking heater as an option and then when you get in the car in parking heater mode just leave it running. If you are concerned about forgetting to switch it off you could also consider using a timer relay

Whichever mode the heater is in it should ramp down around 71c and then go into idle around 77c, most people who use their heaters in parking mode will get in the car before the temp reaches 71c because they will only be left about 15/20 minutes which is usually enough to get the cabin warm and defrost the windscreen but it wont be at 71c by then. If you are not sure if your coolant is getting to 71c why not use the onboard diagnostics via the trip meter, option 19 then 7 to see coolant temperature during your journey