B1108: electric heater fail 1

Hi,

I have an issue with the PTC heater. It works if I do the preheating with the remote. It also stays on when I go driving afterwards.
If I don't use preheating then the heater doesn't produce any heat while driving.
If I use OBS2 dongle and hobDrive I can see that in the beginning the heater is drawing 5820W and after a few minutes the power consumption will drop to zero and I get the B1108 DTC. if I keep clearing the DTC-s I'm eventually able to get the heater to stay on, but this will take 20 minutes or so.

The car is a 2012 model.

Do you have any ideas on what could be cause of this issue?

That code is thrown if the controller does not sense that the heater is getting hot after about 20 seconds. The first troubleshooting step is to check the level of the fluid in the heater loop. There was a Service Bulletin with some corrections to the troubleshooting manual, here is link: MSB-12E55-501A

kiev, thank you for the corrected manual pages.

The fluid level is ok. The pump is working. Everything is working on AC power.

Recently I had a chance to drive a 2012 Nissan Leaf. The heating seems 10x more powerful than on the i-Miev. So I’m thinking something must be wrong with the PTC heater.

I finally replaced the heater and that fixed the issue. I’m currently dissecting the old heater to see what failed. So far the electronics seems that be fine.