The gas models do have a fan to ventilate the module box under the hood. I assume that your module box is on the left, whereas they are on the right in the US. Hopefully the procedure is the same, and someone can come up with it for you.

I've never heard of one going bad, but any fan can break. I assume that you need it or it wouldn't be there. The fan is not present on the IFI diesels.

 

Yes it is petrol and ecu box is on left hand side. I had to remove a small two wire connector going to the fuse box within the ECU module box and then replace the blown fuse and then it started perfect. Merc Specialist said the wires run to a fan that would need to be replaced. By leaving it disconnected and replacing the fuse was enough to get car started and me home.

Any help on doing job would be appreciated.

Thanks

MFK

 

Stripped out the fan this morning - you have to release all wires to the ecu's and then unbolt the mobule box (4 bolts). Then there are another four bolts to be taken out of a housing attached to bulkhead and you can then get access to small fan which is mounted on side of this housing. A bit fiddly but ok - now all I need is a fan

Cheers

MFK

 

A fiddy PIA, for sure

...unbolt the module box (4 bolts). Then there are another four bolts to be taken out of a housing attached to bulkhead and you can then get access to small fan which is mounted on side of this housing. A bit fiddly but ok - now all I need is a fanMFK

I'm not sure what fiddy means (neither does my spellchecker :grin), but it sound quite descriptive--I like it! Pulling the box in my 2002 E320 was a wicked PIA for sure. You will need some looong extensions and a socket swivel to get at two of the bolts on the firewall...er, bulkhead. Thanks for the info, lad. I wasn't quite sure how many screws were hiding about.

Now I'M looking for a fan!

 

This is one to remember. It would seem as if there is some protection build in to prevent the ECU from overheating when the fan stops working. I would assume that the variety of problems you encountered were due to the ECU starting to overheat and the electronics not operating properly. I've experienced similar problems when the fan died out on my PC and the CPU overheated.

I've checked the fuse list and could not find any description for the fuse that you had to replace, Can you remember which one it is? Also how was the problem diagnosed? Any codes? Most people would have assume the gearbox or CPS gone bad.

I can imagine the end result if one had to take the car to a dealer. Probably a bill of several hundred dollars, if not in the thousands, and a full ECU replacement.

Any further information on this would be appreciated, as well as any pictures.

PS. I hope you bought the Merc expert a few pints.

 

Was it the

K40 relay?
Control Module
that blew?and have you tried to power the fan and see if it is actually dead or did just the relay die?
ohlord:bowdown:

 

Ah, the infamous K40 module. On the R170 (SLK) forum, is was virtually standard practice at one stage to remove it and re-solder some connections. Probably more vibrations on the SLK combined with a bad batch of K40 modules caused frequent problems with solder cracking.

 

No it was a standard 10Amp fuse that blew in the fuse box within the ECU module box. The small fan has 2 wires (red and brown) going to it and it is plugged in to the end of the fuse box holder -the fuse kept blowing until this fan wire was removed. I now have it running without the fan and a 5 amp fuse in it until I get a fan.

See 5 amp fuse I have put in on Right hand side of photo. The fan wire plugs into this same block but further down to the right of picture - not shown in this photo.

It was a brilliant diagnosis (over the phone I must add) by the specialist. He mailed it in seconds once i described teh sequence of symptons etc.

 

This is the fan that has failed. Any idea where I can get one - Main Dealer wants €180 . No luck at scrap yards so far. It just screws onto side of the ECU box at the bottom.
Part No. 2105450595

PA66-GF20-GB10 is written on the casing of it.

It also says TYP RV40-18/12GU-013 13.2V

Any help much appreciated
Thanks
MFK

 

This is probably going to be a dealer or scrap-yard only item. Voltage is wrong for PC spares. You can maybe also check if VW or BMW are using the same part. Sometimes they share the same parts, but at a more reasonable cost.

 

Thanks will try other German cars!!
What would the voltage be - assume 12V but 13.2V is what it says on the part itself. It is an MB label but has Papst as a manufacturer - I have tried contacting them directly but no answers yet.

Regards

Matt

 

12 Volt cars are actually 13.2V. Confusing but a fact.:surrender:

 

Slight thread derailment here, but I've never, ever seen a fan on my E320 ECU here and I've replaced the ECU.

Is this a new development in the second gen W210?

 

Wow, this is an old thread. Don't think I saw it before I replaced/repaired my blower.

I know diesel don't have the blower and for UK cars, MB suggest unplugging it. But whether pre 98 cars have it, I don't know. But you could check that easily enough on epc.