Can't stop my MM175... HELP

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I've posted this question in the *ahem* "other" forum, but want the opinions of the experts here as well.You might remember I had to work on the trigger of my MM175 before. Well, new problem now: half the time when I let off the trigger, it won't stop welding. It keeps feeding wire and stays hot. I've disected the trigger again, and it looks absolutely fool-proof. I've even insulated the terminals so there is no way it is shorting against anything inside the gun. The trigger is not sticking anymore, it comes all the way back off, and there seems to be no way for it to not break the connection when it does so. Any ideas? I know that if the problem is in the trigger, the gun is out of warranty. But I'm wondering if it might be in a relay somewhere, in other words, in the box, which is still under the 3-year warranty, right? I opened the box and could see nothing obvious, so went no further until hearing from the experts. I'm in the middle of a job where this is the machine of choice, so time is an issue.
Reply:Mac,I vaguely remember a thread (probably on the Hobart forum) where there was a similar problem that wound up being caused by bare wires from the trigger down  inside the cable housing.  You could check for that with an ohmmeter across the the leads if you remove the gun from the welder and wiggle the cable around to see if there is an intermittent short.Other than that, sounds like a stuck relay on the circuit board?If it's not the trigger wires, sounds like time to call the factory to me.
Reply:Mac, have you accessed the roadmap for the machihene on Millerwelds.com?I haven't looked at the map but I seemt o recall that machine is solid state control, no relay.Most likely candidate, there is a short in either the gun or cable, but without being hands on with the machine, it's nearly impossible to diagnose.Appreciation Gains You Recognition-
Reply:Yeah Franz, that makes sense.  I'm going to do the ohmmeter thing this afternoon.Also, I'm going to weld until it sticks and then pull the trigger cord off the machine and see if that makes it stop.  If I can do it before it fixes itself, that should tell me if it's in the gun or board.  If it's in the gun, it should be a cheap fix.   And if it's in the board, it's under warranty.  How often does it work out THAT way?
Reply:Sounds to me like it's the circuit-board.........I'll be the LAST one to let you down !
Reply:Go figure, it REFUSED to malfunction last night.  I welded an entire security door together with no problems when only two nights ago I couldn't tack it together without spooling wire all over the place.
Reply:That sounds perfectly reasonable to me.  But I bet you will someday soon see it again.  I still think it's likely to be a worn or thin spot in the the trigger wires, in the insulation, but I admit it's just a hunch.
Reply:Mac, even a Gooburmunt employee oughta know it ain't gonna screw up when you're ready for it to so ya can fix it.Appreciation Gains You Recognition-
Reply:Okay, it did it again yesterday afternoon, and it was kind enough to stick long enough so that I could yank the plug and it would stop, put the plug back in and it would go again.  This confirms that it is in the trigger or wiring to the trigger.I pulled the trigger out further than I ever had before and looked at as much of the wiring as I could.  It had some flattened spots in the insulation, from where they were twisted around each other, but didn't really looked damaged.  I carefully rewound them without twisting them and replaced the trigger.  So far so good, but I've been there before, too.