DPDT switch burnt while off

[lincoln8o8]

Hello, I wired a DPDT switch to my sunroof 12v DC motor. It was working ok and I was able to reverse the polarity of the motor to open and close the sunroof. However days later it started to burn when off, even though I hooked up a 20A fuse before the switch. I don't know if it's a short circuit or the fuse was too big, or wires to thin. Any help or suggestions could be useful.

 

[Lucien Nunes]

Sounds like moisture ingress or an internally damaged / shorted switch, as it seems there was current flowing when it was supposed to be off.

What was the rating of the switch and the motor load currrent?

 

[lincoln8o8]

Sounds like moisture ingress or an internally damaged / shorted switch, as it seems there was current flowing when it was supposed to be off.

What was the rating of the switch and the motor load currrent?

I just checked, switch current rating is 15A. Unfortunately I don't much going for the motor load current. I can't seem to find anything on the web.

 

[brianmoooore]

Could it be a design problem with this particular switch? A DPDT switch used for polarity reversal needs to have a definite break before make design to avoid momentarily short circuiting the supply s it's operated.