W123 300D Window Lift

On a trip and my driver's side window has suddenly refused to raise. It keeps blowing its 15a fuse. Prior to failure, it was working smoothly and normally, although I recall an incident last Fall when it
failed temporarily in the "up" position, but then upon arrival in warmer clime, I started using the window without thinking and it worked fine. I have tested the switch by swapping; the switch itself works; and using electrical tester and found power at the positive wire.
Additional note: The rear passenger window switch is missing--could that be any factor, as the two are connected.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
You need both switch to make that window work.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Well, I took the switch connection off left-rear switch and put it on the driver's window switch and activated the switch--the passenger- side window went down and up, no problem, and from that I deduced that the switch itself was OK. I also tested the positive-side switch wire for the driver's side and discovered current there. But window is still all the way down, and every attempt to activate the switch results in a blown 15a fuse for the window pair.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I would do two things...
1. Take apart switch and clean all contacts inside... 6 contacts. This make sure it is not the carbon deposit that is blocking current to the motor... which also increases the current draw.
2. Take apart that door panel and make sure it is not jammed. It is possible that that motor is now too old and draws too much current... so a new motor is your best bet.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Tiger, thanks. The problem turned out to be the positive switch wire. At some time or other, that wire's insulation was stripped too far away from the small wire connector that fits into the switch pot, allowing the wire to come into contact with another terminal or something in the switch--causing it to short. I fixed that, and got everything back together with the right terminal connections, and the window now works flawlessly like it did before.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.