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So I was trying to find out why my blower motor was not working and I found out why. When J have the motor plugged in there seems to be a short because it reads around 2.5 volts with a multimeter when the motor is unplugged and when I plug it in it goes down to 0. I tested the motor with a 12 volt battery and it works fine. Just wondering if there is any reason why it does this. Anything helps. Thanks!
The next thing I might do is buy a new regulator and see if that fixes it. There also seems to be a problem with the holder that holds the motor in place. If there is anything I can try to fix it or find a suitable fix let me know i’ll try it out.
The last thing is that there is no AC. I’m not sure if that happens because there is no blower motor but that’s an issue I think there is.
The regulator is a very common problem. My son has them for sale on his ebay site. “thebenzgarage” reach out to him… he is a walking talking expert on the R129 chassis . thanks Bill
your diagnosis seems logical----you need a new fan regulator
if your fan isnt working it would be difficult to circulate any cold air, that is assuming the AC system is functioning correctly, but you will find out once the fan is working
I went ahead and bought a new one should be here in a couple days. My brother who owned the car before said that it never blew cold air which makes sense knowing the car is almost 30 years old. I guess it’s the compressor for the ac if not the fluid could be the issue. Once i get it put back together i’ll try to see what the problem could be. I’m not sure what to do about the clip that hold the motor on though. I’ll try to figure some way to mount some bold on or something like that. anyways thanks for the help it’s always nice to get it for stuff like this.
The regulator is powered by the A/C control panel. The control voltage is 0 - 5 volts, so what you measured was fine. If you really put 12 volts on the regulator input, it's probably broken now.
In my experience, over time the motor current gets higher and higher due to broken bearings. First it no longer runs at full power because the regulator is cutting out, then later the regulator burns out. I would install an old, good motor with an old, good regulator, the new parts from the accessories are usually bad.
I secured the motor with two cable ties, but the lower bracket has to be modified to do this.
The regulator is powered by the A/C control panel. The control voltage is 0 - 5 volts, so what you measured was fine. If you really put 12 volts on the regulator input, it's probably broken now.
In my experience, over time the motor current gets higher and higher due to broken bearings. First it no longer runs at full power because the regulator is cutting out, then later the regulator burns out. I would install an old, good motor with an old, good regulator, the new parts from the accessories are usually bad.
I secured the motor with two cable ties, but the lower bracket has to be modified to do this.
I installed that regulator and the blower fan works. i saw something on how it can burn out if the fan is loose because that bracket broke so i fixed it on there with some wire and is now secure. I still don’t have ac but i’m sure that was a problem from before. I know there are vacuum leaks and I need to fix them but I am working on that. I have fixed the problem with blower motor so that’s what I went on here for in the first place. Thanks for writing I know there are still things I can probably do to fix it better but for right now Im just trying to get it all working.
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