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View Full Version : Fet question for fet-techs?


xxam
2008.04.03, 09:42 AM
I just did my first fet change. (due to a blistered stock fet) All looks good, it looks pretty clean, however I have no reverse. Looking at the fets with the dot bottom left (motor terminals on top), the fet on the left lost a pad on the board while removing the old one. The pad was on the output right side. All fet feet were soldered together on the output side. Could this be why I lost reverse, or could that only have something to do with the input side? Anything else it could be?

thanks in advance

Spoon
2008.04.03, 09:49 AM
If everything on the motor terminal side is soldered together you should be okay. From your description it sounds like that's the side that lost the pad.

I would check all of the solder joints on the other side, pins 1-4, on the bottom in your description.

If any of them look questionable just touch a hot soldering iron to the point where the leg contacts the pad, trying to heat both at the same time. This should let the solder flow and give you a good joint.

It's hard to say exactly what's wrong without a good picture but I hope that helps.

xxam
2008.04.03, 10:48 AM
Thanks spoon, I was in the process of taking a close up photo to help my post, and looking at the photo as a close up (better than my magnifier), I saw one of the feet
(pin1) looked like a problem. I did just what you suggested and TADA...reverse is back! My first fet change/upgrade was successful!