Ironically this notification popped up just as I was going to check the Sprinter which I do weekly, I have had both types for three years now one Ctek and four of the bm2, the hardware has been fine, but the bm2 app is far superior. Being ble they don’t have massive range but otoh use very little current which is important.

Is yours an Eberspacher/Webasto or one of the Chinese Clones?

@@CriftinsCampers It's the Eberspacher Keith. The fan is also making a High pitch noise, not too loud but still annoying. Sometimes it seems to quieten down though. I'll need to take it out and check it, it could be the bearings. The inlet got blocked by something a while back and the heater shut down. There was a slight smell of overheated plastic but it disappeared quickly. After an hour I restarted it and it worked fine plus no smell but it's perhaps caused the issue?

@@pa_maj.MARTINI-van-MAN Is it a D2/D4 or one of the earlier models that I am less familiar with? A D2/D4 with a decent controller like the 801 should modulate down to a very low fan speed and draw perhaps 1A or so tops. until it ramps up to add heat, flat out my fan draws around 4-5A iirc. Typically the max current should only be seen during startup and shutdown if the controller is doing its job. There can be exceptions though if the van get too hot the heater will completely shutdown and on restart the glow plug and fan at max will come on. the fan motors are pretty expensive for Eberspacher but clones are cheaper from Dale Maltby note the D4+ black fan is larger and only uses one speed sense magnet I bought a D4 motor and fan assembly by mistake but it was easy to swap the fan over. if yours is an earlier Eberspacher have a look at this site. www.letonkinoisvarnish.co.uk/eberspacher_intro_1.html

@@CriftinsCampers I went out to the van and checked Keith, it's fitted under a seat in the back so had to use my phone to take a picture of the label with my phone to see it lol. It is the D2. That's what happened Keith, it gets too warm then turns off then restarts when the van cools down again. My van is not what you would call well insulated and there are a lot of vents so temperature control is difficult, a setting that works one night might not work the next; I feel like a dog chasing its tale with the manual non digital display controller. I was hoping some silicon grease on the bearings in the fan would work but to go through the work for a short lived outcome would be silly. That's a handy link Keith thank you.

@@pa_maj.MARTINI-van-MAN the motors do get tired one of mine did squeak at very low speed I used some white grease on it but it didn’t last long as it was the one where brushes were also completely worn out so I replaced it. Cheapest place I have found for an 801 is here, I have bought two from them so far. www.melloronline.co.uk/Heater_Controllers/731/Eberspacher_801_Series_Modulator_with_Diagnostic_Readout.html

All these voltage display type gadgets are a complete waste of time for measuring the soc of a lead acid battery. To do it accurately requires a shunt based monitor that can do accurate two way current measurements. For me the best feature of these is the details in the graph, I can see for example exactly when my fridge is cycling on and off etc