How to test Tranny solenoids?

[imq707s]

I want to test the EPC solenoid and the other shift solinoids in my tranny on my 97' Mountaineer. I'm pretty sure it's got the 5R55E transmission in it.

Are the solenoids all 12v DC? Can I just give them power and listen for a "click" to know if they are working or not?

Thanks

 

[Glacier991]

you want to test the resistance as well as apply 12V and listen for the click. The EPC solenoid is one that can "work" under those tests but not be doing its job properly... it's not a simply on and off deal with it.... if you have a lot of miles and are in there, it may not be a bad idea to replace it. Your 4 shift solenoids should be between 22-40 ohms... but most I check, including new ones run between 26-30.... I'll have to check on the EPC and TCC, those resistances do not immediately come to mind., Thery are in the 5R55E Valve Body Rebuild Diary.... it's not in the useful threads but should be findable in the Under The Hood and Driveline forum.

 

[budwich]

As indicated, they are solenoids... not relays so they aren't "just an on / off". Their operation is intended to mechanically cause something to happen. If they don't have enough force to cause that operation (ie. shift lever / pin, etc) then even though you hear a click sound, it might not be successful under "normal installed operation".

 

[Glacier991]

well, actually these solenoids are pretty much on off. The only thing that moves is a plunger inside them to allow or not allow fluid to pass... the "click" test is recognized by FORD as an acceptable test method for all but EPC solenoids, and even then it is a tool. Gunk in solenoids is the biggest problem... and why there are multiple screens to try and keep it out. The best thing to do is pull them and while exercising them with 12V DC blow brake cleaner thru them, and follow that up with vb teflon lube before you reinstall them.

And to a degree you are right, the "click" does not tell the entire story, but it is a good indicator of a "live" solenoid. But do not think that these solenoids are moving anything external to their own bodies, cuz they ain't.

 

[TheJMan]

I'm pretty sure it's got the 5R55E transmission in it.

If I recall correctly, the 5.0L was the only motor offered in the 1997 Mountaineer. If that is the case, then you have a 4R70W.