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OHM Measurement for SM 31-900DC - Red's Head, Roadshow

bluejonny

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10 Years
Joined
Jul 21, 2011
Messages
298
Location
Southampton, UK
Hello everyone! Question - I have a suspected dead coil. I stripped out Red's head as her eyelids were not working, and all the other coils fire when I put my bench power on them. However, the one that controls Red's eyelids, listed as an SM 31-900 DC, doesn't fire but I can find no information on what's its resistance should be so I can measure it. Anyone know what it may be? I don't have a spare and the others in the head are a different type.

Thanks in advance.
 
OK< replying to my own thread. Appears the solenoid had a broken wire (so small could hardly see it with the naked eye.) A bit of fixing and resoldering and we're all good. One other thing, is that my bench power only gives out a maximum of 20v, so not enough to pull the plunger in as it's out a long way. That's a note to myself. :)
 
I found this in my paperwork but it’s doesn’t have your coil but it might help .
In order to check coil resistance put your DMM on its lowest resistance setting then put the DMM red and black leads on each coil lugs. The coils can usually be checked still in the game without having to disconnect any wires . A resistance of two ohms or greater should be seen anything less than two Ohms and the coil is bad.
 

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