W124 '95 E300 intermittent blower fan operation.....
 

And it only made 102 today!!! :flamethro

OK, I've never had any issues with this car. Today was completely out of the blue. Youngest daughter and I cruised to Fry's to look for part of the wife's birthday present {Elvis movie box set}.
The air conditioning worked fine on the way there. Started off in auto and moved to low fan speed on the way there. We went to leave, turned on the AC and no fan!!! The compressor was on, and when I was moving, cold air would ooze from the vents. No matter what combo of buttons I pressed I got no blower fan. Even stopped, turned the car off/on, still inop. Great! I figured I blew a fuse to it.
Fast forward to this evening. Went out and started the car. Turned on AC, fan on auto, and it came on and blew cold air. I turned it to low fan speed and that was it. No more fan, no matter what.
I looked for the fuse. Fuse box cover said blower fan fuse was "outside" of fuse box. I found a strip fuse right in front of fuse box that looked like a glow plug strip fuse. It did not appear cracked although I will remove it now that I believe that is a fuse for the fan. [yea search function]
Is there anything else I should look at? Would seem an odd failure for the CCU, but who knows with those things.
Any ideas anyone????

BTW, if I had taken this car to the GTG today it sure would have ended up being a hot trip!!

**Duplicate post from Diesel Discussion. Just thought somebody with a gas version of a late model W124 might have info but not see a thread in Diesel Discussion.** :)

Leave in AUTO position. Problem solved.


Cold spell starting Sunday........

http://icons-pe.wxug.com/i/c/a/partlycloudy.gif
Sunday 97° F | 74° F

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Monday 95° F | 70° F

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Tuesday 97° F | 74° F

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Wednesday 99° F | 74° F

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Thursday 97° F | 72° F
Partly Cloudy

When my regulator started to go, it would exhibit this kind of strange behavior too. Usually it didn't work in low. It would work sometimes in auto and sometimes in high. At other times it wouldn't work at all. I would start by taking out the strip fuse and checking it closely. Sometimes it can look good but it is actually cracked when you take it out.

I bought my replacement from Fastlane. I was always amazed at the engineering that went into the MB blower regulators. Too bad they couldn't have engineered them to last longer.

Well, that certainly sounds quite similar. Where is the blower regulator? {still learning the W124 lay of the land.....}

Sounds like it's a worn out selector bar brain going out. Probably not more than two to three hundred dollars for a new one, or scour some junkyards for one cheap, that may have some life left in it. At your car's mileage and age, it's the likely item to fail, from what you are describing.

Is the "selector bar brain" the CCU assy.? {push button assy}

I guess I need to see what years of W124's have the same fan regulator and CCU assy......
PNP in July!! Good grief...... :flamethro

Well, what do we always tell folks about glow plug strip fuses? Pull it out and make sure it isn't cracked!!
Well, the blower fan strip fuse would be the same way.

Looked perfectly fine just sitting there. And I looked closely!!
http://i29.photobucket.com/albums/c2...Fanfuse001.jpg

But upon further examination:
http://i29.photobucket.com/albums/c2...Fanfuse002.jpg

It is a 30 amp strip fuse that I'll get from the dealer I guess. Right now it has an 80amp glow plug strip fuse in it. :eek:
At least it isn't my daily driver. Matter of fact I'll probably just order the fuse since I doubt I'll drive the thing for at least a week.....
Thanks as usual for the fine assistance. :)

Yes, if that is the technical name of the part. Mine went out in my '83 300SD at heck, 200K miles or so. It was diagnosed by Mike (shop foreman) at Park Place MB on Oak Lawn years 'n years ago. You can tell that is what it is, because other things on the bar work. The button's connections (contact points) get worn out after so many hits on them. The new one worked perfectly for the remaining years I owned the car. The part was somewhere in the vicinity of $100+.....but it's been so long ago, I don't remember how much it was. There was no place reliable to shop prices then, as the Internet is today.

I had the same intermitent problem on my 92 300CE. I did replace the 30 amp strip fuse which was cracked in half and all was well for a few weeks. Then the fan quit working all together regardless of the setting. The fuse was fine. It turned out the blower motor was bad. Had it replaced and worked great ever since (one year ago).

That motor is not cheap and you need to be very careful removing the squirrel cage fans if you want to reuse them to save $$