Can you fry a solenoid?

[MSHardeman]

Jack,

I'll definitely check my ground tomorrow, but it doesn't make sense to me that the popper would work, ground and all, for a few months and then suddenly it wouldn't. Maybe the ground wiggled itself loose, but I could swear that I had checked that before. Guess I'll find out.

Thanks.

[pbkid]

Jack,

I'll definitely check my ground tomorrow, but it doesn't make sense to me that the popper would work, ground and all, for a few months and then suddenly it wouldn't. Maybe the ground wiggled itself loose, but I could swear that I had checked that before. Guess I'll find out.

Thanks.

ya, like i said, im not an expert by any means about selonoids...so its just my objective opinion...

grounds have a tendency to loosen up because lots of people use self-tapping screws which DO loosen up over time...

even I, after years of installing was using self tapping screws until i became MECP certified, now i realize that they arent the best solution. anyhow, try to check the ground, it may just be a bit loose and there is all your problems...also, did you use a star washer when you grounded?? they help to 'cut' into the metal a little to make sure you get a solid ground.

http://www.midwestmil.com/lockwashers.jpg

let us know how it works out..

[Triathlete]

yes you can fry a solonoid. I changed plenty of them that had gone bad when I was an aircraft electrician. But I would check the ground and wiring first.

[pbkid]

yes you can fry a solonoid. I changed plenty of them that had gone bad when I was an aircraft electrician. But I would check the ground and wiring first.

well....

/eatfoot

[Marlin]

yes you can fry a solonoid. I changed plenty of them that had gone bad when I was an aircraft electrician. But I would check the ground and wiring first.

x2, only on an aircraft carrier in the power plant.

A solenoid is nothing more than a coil of wire, a moveable metal core and stationary core and a spring. ALL current flow creates a magnetic field.(Thats how a junkyard crane works) When current flows through the coil (when you close the switch, push button etc...) it creates a magnetic field that is enough to overcome the spring and move the moveable core as it is attracted to the fixed core, and voila, that is connected to a pin or whatever and you just opened your trunk or whatnot. When current stops, the spring pushes/pulls the pin back to original position.
This happens to be what I teach here at the Naval Nuclear Power School.
Sorry to thread jack, but blowing a solenoid happens all the time, too much current or heat, friction from the moveable and so on will quickly burn up the coil. The best way to check, use am ammeter (has to be in series across the switch, so that the ammeter becomes the switch, if there is current flow, then it isn't a wiring problem, its the solenoid, if no current, then it could be a wiring/ground problem, or the coil got hot enough that there is an open. Next would be to check resistance, shouldn't be too high, after all, it is just a coil of wire, I would think a couple hundred ohms or so. Just a thought.

[MSHardeman]

Marlin,

Thanks for the explanation. Currently my solenoid doesn't seem to have a spring to return the plunger. If the solenoid isn't hooked to any power the plunger stays at the bottom (depending on which way I have it oriented) and I can grab the wire coming out of the top and pull the plunger to the top of it's stroke. When I let the wire go, the plunger falls back down. I don't remember if this is the way that it always was, and if someone has a popper kit out of the car could you verify this?

I have a volt meter (measures ohms, volts, etc.), but I'm not terribly sure how to use it to check the coil as you describe. I'll re-read your explanation and see if I can't figure it out (I'm absolutely clueless when it comes to electricity, and car wiring in particular). I'm headed down to the garage to take the solenoid out so I'll do the tests soon. I'm also going to pull the solenoid out and wire it outside the car to a good known ground and power source to see if I can't get it to work. If not I'll have to find a new solenoid, I guess.

[Marlin]

To check the resistance, just turn your meter to ohms, looks like a horse shoe, and put the black test lead on one wire and the red test lead on the other wire. Polarity doesn't matter. I would say since your solenoid doesn't spring return either direction, its toast. The spring may have come disconnected, or failed all together.
Here is a decent explanation with pics...
http://mechatronics.mech.northwester...solenoids.html

[MSHardeman]

OK, Jack may get the gold star on this one.

I took the solenoid out and ran one wire to a known good ground and another, through a push button switch, to a fused power terminal in my auxilliary fuse box. Holding on to the wire that comes out of the top of the solenoid I hit the switch and the solenoid worked. Gravity pulled the body back down, returning the solenoid to a ready position. I think this is sort of what happens in the rear door. Since the wire is connected to the door latch (and the latch is spring loaded) the latch returns the solenoid to the ready position.

I put the solenoid back in the rear door, but moved the ground to some exposed metal and ran a power wire outside the VX with the inline switch and fuse. Hit the switch and the solenoid worked like a champ. It pulled the door latch and returned with no problem. I put all the wiring back the way it was and hit the factory tailgate switch that I have installed and.....NOTHING. At least now I know that the solenoid is good and the problem could be a fried switch or relay. My next step is to bypass the factory switch and use the inline push button to see if I can start to isolate the problem.

Marlin, I did test the solenoid with the volt meter (set to ohms) and it would start out high but quickly drop to zero. I have no idea what that means since the solenoid seems to work, or is there supposed to be no resistence? Also, now that I think about it, I don't know if the plunger was up or down at the time of testing. Could that have made a difference?

One thing that was a little strange was that everytime I triggered the solenoid (outside of the VX) there was a small puff of smoke that would come out of the top of the solenoid where the wire exits. It didn't smell like an electrical burn and I'm wondering if it was just dust that has been building up over the past year.

Thanks for your help guys. Hopefully I'm getting closer to a solution.

I LOVE this site (and the VX family).

[MSHardeman]

Aaaaahhhhhaaaaa!!!

FINALLY figured out what was wrong with my rear door popper. Originally I was looking for all of the complicated stuff; blown solenoid, fried switch, toasted relay, but the culprit ended up being a severed wire.

I should have looked at the wiring first because everything was working fine after installation, and the fact that it suddenly stopped working should have clued me in.

I used a volt meter to check that the switch and relay where getting power (they where), and when I pushed the switch power would flow through the relay just fine. When I tested the wire at the back door by the solenoid there was no power. I thought that maybe I just had a bum wire so I started to re-run a new wire using the old one to pull it through. When I tugged on the old wire in the jack cubby it popped right out and the end was crushed and cut.

The wire loom coming in from the door passes through a rubber grommet that MUST be seated in a little niche in a metal plate to the rear of the VX in the jack cubby because if it isn't the door stop pivots into that same area when the door closes. I guess when I originally ran the wire for the popper I didn't re-seat this grommet into the niche and over the course of a couple of months, as the rear door opened and closed, the door stop must have been crushing the wires against the metal plate and eventually cut the popper wire (this could be the issue with someone's rear defroster not working). This time I made darn sure that the wire loom was protected in it's rubber grommet, and totally seated into that niche so, hopefully, this won't happen again.

Thanks to everyone for the advice and the patience, because I know that I've written more than a couple of threads lamenting the woes of my rear door popper.

[Triathlete]

yes you can fry a solonoid. I changed plenty of them that had gone bad when I was an aircraft electrician. But I would check the ground and wiring first.

:bwgr::bgwp:

Glad you got it figured out!

[MSHardeman]

Billy, the ground wire was fine it was the chopped in half power wire that was messin' with the whole works, but YES, checking the wires first would have been the way to go.

Oh well.....live and learn.

[pbkid]

nice!!!

congrats mark. glad you got it workin!