Does anyone know how to properly check the resistance on a solenoid to see if it's good. My tranny's acting funny and I need to see if my shift solenoids are between 20-40 ohms, but I can't seem to get a reading even off a known good solenoid. Thanks!

 

Just measure across the terminals with the meter set to ohms. Test your leads first by crossing them to one another.

 

Thanks for the quick reply, but should this be tested with them connected to the harness? Power on? Disconnected? I tested a known good one (or at least one that clicks when energized) and it's reading 0ohms? not 20-40 like the manual says it should. This is a 1-2 2-3 shift solenoid from the 4l60e btw. Thanks!

 

To measure the resistance of the solenoid coil, it has to be disconnected. You don't test resistance in the presence of voltage or ground. You can do this at the solenoid or at the disconnected transmission electrical plug if the pan is not off.

 

Hmm, I'm reading 0ohms here between the 2 terminals with the solenoid disconnected. I was under the impression that a solenoid is usually good or no good. No real in-between. It does however click if I apply some voltage to it. Hmm.

Shoebox, thanks for all the help you provide this online community. Running the risk of sounding cheesy, you're a real gift to people like me who are just learning. Thanks

 

Be sure you are using the correct scale on the meter (if it does not have an auto-ranging feature). Zero ohms would be a dead short. Also make sure your probes are not touching. Measure another solenoid and see if you get the same.


Thank you.