Temp Gauge sender resistance? 190E 1985

Does anyone know a couple reference points for the resistance of the sender for the engine temperature gauge used in a 1985 190E? (For example, x ohms at 40 degrees C and y ohms at 100 degrees C.) I'm trying
to figure out if the gauge is bad or the sender is bad. The engine is at normal temperature as measured by a thermometer in the coolant, but the gauge is reading way low.
Thanks in advance.
Dave
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It's the sender. It's always the sender. How is the wire going to the sender? Typically because of the vibration they work-harden, crack get oil in there and all sorts of nastiness ensues. First thing I'd do is strip off the last 1/2" of wire and make a good clean soldered connection tothe connedctor then try it.
--
Need Mercedes parts ? - http://parts.mbz.org
http://www.mbz.org | Mercedes Mailing lists: http://lists.mbz.org
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks Richard. I'll try the wire next. Hopefully it's not the gauge.
I was expecting it was the sender, but if I unplug the wire from the sender, the gauge reads minimum. Then if I then ground the wire that was pulled off the sender, the gauge only reads about 40 degrees C. That sounds to me like it's most likely the wire or gauge. Come to think of it, occasionally the gauge bounces around wildly, so maybe it's a break or bad connection in the wire, hopefully near the sender where I can get at it.
Dave
Richard Sexton wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

That test certainly rules out the sender as the culprit...
If you have access to the rear of the gauge you can try running another wire to ground from the gauge and see if that drives it all the way up as it should...
If that works, then replacing the wire to the sender is a good solution. Marty
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yup, classic sign. Both my temperature and oil pressure gauges did this and in both casaes it was the wire's connection to the sender (really easy to fix on a 126)
http://electric.articles.mbz.org/126connectors /
--
Need Mercedes parts ? - http://parts.mbz.org
http://www.mbz.org | Mercedes Mailing lists: http://lists.mbz.org
  Click to see the full signature.
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.