E320CDI (2003) No Heating

[Truescot]

I recently had a flat battery and managed to jump start the car - according to the handbook of course. The car is running fine except I now have no heating any longer. The car warms up to normal temperature and even after a 200 mile drive the heater is still only luke-warm. The local MB dealer suggested I disconnect then reconnect my battery but this had no effect. I did the same with the auxilliary battery but again no effect. Could I have blown a thormostat, a relay or a fuse somewhere and if so where are they?. I can't see anything in the fuse panels (driver's side or boot). There are a few undocumented boxes which look like relays in the boot fuse panel but I've no idea what they are or how to test them and I've no idea where the thormostat is. I'd like to do this myself since the John Weir dealership is notoriously expensive even for minor repairs. Any guidance would be much appreciated.

 

[television]

Hello and welcome,,the pump valve may have stuck, it is low down against the fire wall drivers side and you can just see it, many just give it a whack with a hammer or iron bar and they start running again, mostly with no further trouble

 

[rpe2]

...or http://forums.mercedesclub.org.uk/showthread.php?t=72994&highlight=heater

Welcome to the forum

 

[MB TECH WARRINGTON]

As RPE says it will be that valve, we have done 20+ in recent times.

There is a small motor which due to water ingress fails, poor design if you ask me. Its almost like a scaletrix motor which basically opens a sliding door, bit like a dam, and stops or lets the hot water flow.

The seals fail which allows water into motor. Rusts up and fails.

Depending on how bad, a tap on top may do nothing, although its worth a try.