W140 Fan resistor pack problem..

[DoctorGee]

Hi everyone,

My mechanic told me the Heater resistor pack of my 1994 S280 needs replacing. Both the heating and aircon hardly work as just the draft from the cars motion comes through. Now, he's quoted me £220+VAT for the part & another £65 for labour. I've found this on ebay for £70 brand new( it's "a good quality third party part"..) See the picture atached.
does anyone know if it's the right part?
Where exactly are the fan and the resistor pack located?

 

[chriSTi]

hello I'm curios to know what exactly your symptoms are as i have similar problem, when you turn the heating on are you getting any air at all from dash vents??? I took off the wiper panel on engine bay and on the far right you will see the blower motor with this resistor attached...... cheers, chris

 

[television]

Yes you have bought the correct one,,its 252 in the link, its a regulator rather than a resistor pack.

http://www.detali.ru/cat/oem_mb2.as...GM=717.438&CT=F&cat=19B&SID=83&SGR=045&SGN=01

 

[DoctorGee]

Hello Chris & Malcolm,

I do get the slightest draught. It was bearly adequate to warm the car a few weeks ago but it seems to have deteriorated with the recent cold weather- or maybe it's just getting worse. I noticed that what I do get seems to come from the windscreen vents only now. The fan is silent whatever setting the heating is on.
Malcolm- Do some models have the Resistor pack and others the regulator? Are they interchangable? Must say it's brilliant to have pros like you on the forum..

Greg.

 

[television]

It is only a name,,years ago there was a resistor pack, that was replaced by a regulator around the early 90, but many call it a resistor pack still today.

The one in your picture is the reg pack identical to the one in my link.

Really you should take the fan motor out first and check that your fault is not just the carbon brushes that need to be replaced

 

[DoctorGee]

Hello Malcolm,

I opened the wiper panel in the engine bay to check the motor and identify the regulator. Lo and behold- the fan actually works!.. I don't know if I should do the carrot test or something to check it's speed, but it seems to going at quite a trot. (almost cut my finger when I touched it). I'm still not getting any more breeze through the vents than before though. So it's obvious the fan has been turning all this while. Do you think it's a regulator problem as my mechanic said? or is there a blockage in the vents? or is it something else? Any ideas anyone?

Ps. ChriSTi, have you sorted out your problems with your heating yet? what did you find out? I didn't see the regulator you described- here's a picture of my fan motor as it sits.(Ignore the date- I need to reset it on the camera)

 

[television]

There are 4 speeds i think or might be variable on yours with the reg pack,,does the speed change,,you cannot do a carrot test on this fan. Looking at all of the leaves in your picture, they could restrict the flow,
Reg packs are either good or bad and no inbetween

 

[jberks]

Have you replaced the filters? A blocked pollen filter will stop the airflow.

 

[DoctorGee]

Mine is variable, Malcolm as you supposed. The the flow remains the same whether it's at min. or max. or auto. It gives a good blast when you turn it on and then dies down to barely a draught after a few seconds. This happens regardless of the heat or cold setting. The symptoms are not improved by removing the main filter altogether, so I doubt it has anything to do with the filter being blocked. Are there other filters in the system that I need to change?

Greg...

 

[television]

Then the reg pack that consist of a darlington pair of transistors could be at fault with thermal runaway

 

[chriSTi]

hello Greg , no I've not sorted anything yet myself as I don't drive it every day the urgency is not there, ok then I'm lazy but my missus' aint too happy with cold feet... I don't even get that sudden initial burst of air??? turning up and down the heating feels like its not even connected to ANYTHING.... Think I'll try ebay and take a gamble on the resistor...

 

[DoctorGee]

Hi Chris,

The only reason that I have'nt ordered mine from ebay(http://cgi.ebay.co.uk/Heater-Blower-Resistor-Mercedes-W140-C140-S-Class_W0QQitemZ130244190346QQcmdZViewItemQQptZUK_CarsParts_Vehicles_CarParts_SM?hash=item130244190346&_trksid=p3286.c0.m14&_trkparms=72%3A1301%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318&bcsi_scan_FD92A14AAFC46518=H+KWCcF9p9f23280hdLHkh4AAABx3BQY) is that I wanted to be sure that it is an exact fit for my car. I haven't seen mine yet... Does it sit under the fan motor? I'm going to remove my fan/motor to identify it tomorrow when I get a free moment. If it's the same, I'm going to order it and pray for the best

Greg.

 

[television]

I showed you long ago where it is 252 in that link that I put up, just to one side of the motor and mounted on the motor frame

 

[DoctorGee]

Hi Malcolm!

Thanks for the headsup... The regulator I ordered two days ago arrived yesterday. It came with a soft sealant of some sort and no instructions. Do I apply the stuff to the base of the regulator before I attach it to the motor housing? Any advice much appreciated.

Greg...

 

[television]

This is not a sealant, its a paste to ensure good contact with the face side that is screwed down to the motor plate. this plate acts as a heat sink and extends the area of cooling, the cooling takes place through thermal runaway at the outer edges of the mounting plate, so just put a good coating on the face down side of the regulator and screw it down so that its tight

 

[DoctorGee]

Hey Malcolm and Chris and anyone else out there with a blower regulator problem- I installed my regulator yesterday and it works! So good to feel the warm air powering out from the vents...
Thanks so much Malcolm and everyone who gave advice on this thread- it's been brilliant.
Chris give it a try- keep the missus' toes warm in your classy chariot

Greg.

 

[chriSTi]

happy days Greg, nice one I'll get on it now......

 

[shayes]

Hey Malcolm and Chris and anyone else out there with a blower regulator problem- I installed my regulator yesterday and it works! So good to feel the warm air powering out from the vents...
Thanks so much Malcolm and everyone who gave advice on this thread- it's been brilliant.
Chris give it a try- keep the missus' toes warm in your classy chariot

Greg.

Sounds like I may need one of these. When the car shows temp as 25 its not especially hot and I would think that it should be. There is warm air from the side vents but not the centre vents even when selected. Mind you I only bought the car late yesterday and it was warm enough coming home. Don't think the blower was particularly ferocious when on max but thought that the silence was just another "quality feature". The seller said that he has spent a considerable sum on the air con but its WARMTH that I want, being an old codger! Must get out into the cold to check all the settings but not got a handbook for reference. Should be straightforward, I guess. Teething troubles, nothing to get too excited about -he says hopefully examining his empty wallet..

 

[dragon]

You are not supposed to get warm air from the central vents, only outside air. Warm air only from side vents. If it too cold, close the center vents. Read the owner manual.

 

[shayes]

You are not supposed to get warm air from the central vents, only outside air. Warm air only from side vents. If it too cold, close the center vents. Read the owner manual.

Just come in from sitting in the car in the rain and there is warm air from the side vents. Not sure if it goes as high as 30 degrees. Fan seems to work fine. The central vents have a blue dot switch and a red dot switch. Assumed that they can be hot or cold but you say not?
Not got a manual sadly but already sourcing one.