I have a 1988 190e 2.3. I had a problem with the climate control system where no buttons were pushed and fan was blowing. I replace the climate control panel and for a couple of months it ran fine then it started doing it again where no buttons were pushed and the fan was running. One thing I did notice when I hit a bump it will cut off momentarily and then continue blowing.
Is it a loose connection? Did the climate control I bought on eBay go bad again? What should I look for? Appreciate the help. FYI, I did replace the blower fuse, the metal strip type fuse but same results.

Replaced relay related to climate control. No difference

Replaced brushes in the blower motor, same problem! Help! Is it time to replace the entire blower motor? Ideas? SOS!

I know this controls sometimes have to be rebuilt.Some catch on fire because of a motor on the firewall.Some people put a 1 amp fuse on that wire.

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If it's an '88 and has the pushbutton unit, it'll be the same as the 126 and 124. They don't catch fire like the earlier units do, they're solid state from the 1986 year model instead of mechanical in a 2-part job like the '80-'85 cars were. You likely have a failed blower control module, it's a transistor pack with a heatsink on it. No idea where it is on a 201, on the 126 it's in the blower housing so it gets airflow. If your brushes were bad, it likely caused it to fail shorted, so it'll run the fan any time the key is on, regardless of what the pushbutton unit tells it to do.

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Hello Joe,
page 304 is you wiring diagram.
https://www.scribd.com/doc/157861658/W201-Wiring-Diagram

When the blower is running at what speed is the blower spinning, 1 2 3 or high and does the blower switch change the speed?

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Paul

And here we are again, confused between different years and models. There's no electronic blower control. 201's have a resistor pack, it's located in the compartment behind the battery. Probably unrelated to this problem. I would start by checking the switch itself.

Thanks everyone! I hope to address all the questions,

Paulwho, the blower is running at Max with no buttons pushed. The blower switch does not impact the speed when in that condition exists. Thanks for the diagram! I'm studying up.

Diseasel300, old brushes weren't bad at all. Replaced them anyway as I had new ones from Mercedes Source, The "blower control module" you talk about, Is that the same as the blower control resistor? I know its located behind the battery

Since it runs on high
1) possible broken/loose contact in the relay for high speed, built in the blower switch, shown in the upper left of S3/1 blower switch very possible
2) the white/yellow wire pin 2 is grounding at times doubtful
3) the pushbutton panel is wrongly supplying the ground doubtful

Depends on how much fun you want to have on the diagnosis

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Paul

I've got a blower control switch on the way, stay tuned! Thanks for all the input!

Blower switch was bad! All's well now! Thanks for all the help. I really appreciate it!