NoelC220

Hi all i was hoping someone could help me with this issue.

I purchased this car 3 months ago and the interior blower fan never worked on any setting, the control center seems to work fine and if i drive at motorway speed i can feel the warm air coming from the vents.

So i decided to have a look at the blower fan and popped the cover off at the engine bay so i could spin the fan, it was very stiff so i ordered and fitted a new blower fan this did not fix the issue but needed to be done so i moved on the blower motor resistor or regulator pack (hedgehog looking cooling fins) when i removed the base of the unit i seen burn marks and signs that it had let the magic pixie smoke out. i ordered and fitted a new regulator still not fixed but needed to be done.
I have checked all fuses in the boot and in the engine compartment fuse box and they seem to be fine, using a multi-meter i get the voltages from 3 volts to 10 volts from the control unit when selecting the different speeds, but the main power in to the regulator has no power on it , so my though now is the pre fuse box?

I seen the 3 bolts on the top of the prefuse box and i got 12 volts from each could it still be the problem, or any ideas?

Many thanks in advance for your help

NoelC220

So funny I changed out the fan as it was stiff to spin changed the regulator checked all fuses and I was stumped ......

I decided to chase the pre fuse box and there she was a blown fuse , on a side note I noticed Mercedes in there wisdom upgraded the fuse from an 40 amp on the older models to a 50 amp I am to assume this was a major issue. Check out the photos below I hope this helps someone going forward

Oh and also when removing the prefuse box remove the battery and the box can fit under the air con pipe for easy access to the nuts on the box