450SLC Power Window Problem

The car: USA 1974 450SLC
The problem: no power getting to all 4 power windows.
I've found that there is no voltage getting to the 2 window lift fuses (
#3 & #4) at the fuse block in the passenger's foot well (with ignition key in position 2).
According to the wiring diagram in the original Mercedes Shop Manual, these fuses are fed by the "Window Lift Relay". I cannot seem to find any reference in the manual to the location of that relay.
There is a picture in the manual identifying the 6 relays just above the fuse block, but the Window Lift Relay is not one of them.
The question: Does anyone know where the Window Lift Relay is located on this model??
Thanks much for any help.
Bruce
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Before you even go find the relay. Take those fueses out and put a new one in.
Then take your switches apart and clean all the contact points inside it.
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> GUEST wrote
> The car: USA 1974 450SL > > The problem: no power getting to all 4 power windows > > I've found that there is no voltage getting to the 2 window lif fuses > #3 & #4) at the fuse block in the passenger's foot well (wit ignition > key in position 2) > > According to the wiring diagram in the original Mercedes Sho Manual, > these fuses are fed by the "Window Lift Relay". I canno seem to find > any reference in the manual to the location of that relay > > There is a picture in the manual identifying the 6 relays jus above the > fuse block, but the Window Lift Relay is not one of them > > The question: Does anyone know where the Window Lift Relay i located > on this model? > > Thanks much for any help > > Bruc
Yes indeed. Most problems with electrics are the ol
corroded fuses and switches.You can buy a set of copper ones on eba and replace all of them Go to ebay and copy this number: 320141369355    It'll bring you right t the fuses I replaced mine on my 560 and had plenty left to do my vw bu too....all for $11.00
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Tiger and mus098,
Thanks much for both your replies. I'm aware that 90% or more of these problems ARE caused by the fuses or switches. I have eliminated those possibilities first.
The fuses are clean and have continuity. I then used an auxiliary battery to feed the downstream end of the fuses and the windows will raise and lower normally. Thus, the problem is UPSTREAM of the fuses (ie, toward the battery). To reiterate, there is NO voltage reaching the fuse contacts.
I've also checked to see that the fuse that feeds the coil of the Window Lift Relay is indeed getting voltage when the ignition is in position #2, so the odds are that the relay is the culprit in my case.
The question remains: Where is the Window Lift Relay located?
Thanks again, Bruce
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Usually in the fusebox... I am not familiar with your car.
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