Fuse
 

'93 s320 benz

135,000mi

the heater blower motor will not shut off. I have tried everything I can think of. I finally had to disconnect the battery to protect it. What I would like to know is which fuse can I pull that will shut the motor off until I can get it serviced. I know that there are two fuse boxes, one in engine comp and one in trunk. But for the life of me cannot read/decipher which one will do the trick. guess I should get new glasses also.
Thanks, Michael

If this is build up like an SL, there will be a 3 wire connector / terminal strip just behind or to drivers right of the power brake booster for the fan controller. There will be 2 large and 1 small wires. Near as I can tell the fan controller ( which sits atop the blower housing) is just a power transistor.

On the R129 SL you can see the controller by pulling the cabin air filter located under the hood.

Now I am confused. This is a 140 style sedan. It is a straight 6 cyl. I am not really mechanically inclined on this car. So something easy like removing a fuse is my best rout to take. I don't want to cause any more problems for a mb technician.

You can find a W140 fuse card image here. You might want to print it out. Often MB uses more than one circuit per accessory so more than one fuse might have to be pulled.

http://www.benzworld.org/forums/w140-s-class/1465747-experience-fuse-boxes.html

thanks Richard. That should help some.

There is no fuse for the blower motor. You need to get to the blower and disconnect wire. Be careful - the RED power wire is always hot, un-fused. Leave it connected to the motor. Disconnect negative blue wire.

The pic really helps.tks. Now Is this in the front seat foot space or do I access this from the engine compartment?

It's in the engine compartment. Read this:
DIY Blowser Regulator Replacement and Diagnosis... - Benzworld.org - Mercedes-Benz Discussion Forum

Thanks. That is prefect directions for me.

This is built up differently than the SL but the concept is the same, the black box at the top of the pic with yellow numbers is the fan controller module. The black plug to the right could also be disconnected to stop the fan.

My blower was stuck on high heat and would not turn off. Turned out to be a bad climate control unit. Found a couple of them at local Pic & Pulls for as low as $16.99.