Webasto cabin heater not working

[Sisu9]

My Webasto engine heater on my Defender works but the cabin heater doesn't. There's nothing flowing through the pipes to the unit and the fan is not circulating.

Does anyone have any experience of these? Thanks.

[HelldogBE]

Can you hear and smell the heater burning diesel for a short moment?
If so it's usually the electric coolant circulation pump that's gone, causing the heater to go into safety as the local coolant exceeds safe temperatures

[Sisu9]

Yes, I think that's the case as I can smell coolant (maple syrup type and/or diesel). Is the pump a DIY fix or does it need to be replaced?

Edited by Sisu9 on Monday 14th February 19:41

[HelldogBE]

Sisu9 said:

Yes, I think that's the case as I can smell coolant (maple syrup type and/or diesel). Is the pump a DIY fix or does it need to be replaced?

Edited by Sisu9 on Monday 14th February 19:41

I'd definitely check if you can hear/feel it heating up with a cold engine and quitting after a few minutes.
Pump needs to be replaced AFAIK. Official Webasto pumps cost 150-250 quid, but autodoc offers cheaper pattern parts.

First order of the day will be determining what system you're running. The official documentation and service parts lists might help with that:
https://www.techwebasto.com/documentation/heater/s...

[Sisu9]

I had another check this morning and coolant is flowing through the pipes to the cabin heater but the blower is not activating, The engine heater is a Webasto Thermotop C and the cabin heater is a Siroco Terere 12v 2 speed.

I did note the Siroco had a 20amp fuse in it when it's supposed to be a 7.5amp. So will change the fuse and check that power is getting through to the unit as the blower turns freely by hand.