W203 220 CDI - Engine Temperature

[Wully]

All

A while ago I replaced the thermostat due to low engine temperatures and as a result I saw around approx 90 degrees at full heat.

However with the recent cold snap I can't seem to get the temperature to rise above approx 70 degrees and I'm thinking surely the stat can't fail in such a small period of time.

So to see if there was anything going on I stuck in on DAS and I have a current and stored fault as follows:-

B1003 Component M13 (Heating water circulation pump) or the line to the
component has a short circuit to ground or open circuit. Component
M13 (Heating water circulation pump) is not installed. Ignore fault
code if it nevertheless occurs.

I ran through an activation test and the pump is coming on when prompted.

Could this be related to the low temperatures I'm seeing?

 

[kwakdonut]

70c sounds fine in this weather. My 320 just about gets to 80c in my 12 mile run to work in the morning!