AC and Heater Blower dead ?

[DanielW]

What should I check first? The blower fan does not run at all. Cannot find a fuse that controls this. Exactly where is that fuse located. The card says, "outside the fuse box" , But where? The AC conpressor runs, but I turned it back off quickly since that would not be good without the fan working to take away the heat. Prev. owner replaced the switch push button unit about 50K miles ago. Before, while the blower was still running I would hear a squeek sometimes especially when the outside temp was really cold.

Any advise would be appreciated.
DanielW

[DanielW]

The fan not working post was on an 87' 300E

[fz500sel]

Dunno for sure but you should be able to test the blower itself to see if it is ok. You should be able to disconnect the terminals going to it and jumper 12v to it. If it turns then you know it works and is not bound up, brushes ok, etc. If not it is easy enough to replace.

The blower I believe should be under the passenger side of the dash/footwell. It may not be the case.

As for the location of the fuse, maybe a fellow 300E member can give you some advice.

Good luck,
Frank

[stevebfl]

On the 124 the blower is rather hard to get to for circuit testing being under the wipers in the engine compartment. There is lots of diagnostics in the archives. Basically you must verify the fuse which may have been relocated outside the fuse box. In the center of the dash is a three prong connector which allows easy access to the next step. Without a wiring diagram I forget the exact testing except to say that the transistor blower regulator controls the current through the negative leg from the motor in relationship to a voltage signal from the pushbutton controller (the regulator is under the blower). The signal wire is one of the three wires easily accessible. It should be a 1v to 6v signal with high blow being the 6v signal.