Devo 6 died suddenly

I bought a Devo 6 second hand and flashed it with deviation firmware 3.0. I was very happy with it and it died suddenly one day. When I turn it on, only the blue light briefly light up for half second then nothing happens.
I have fixed its battery leak problem following the online instruction and it worked without any problem for two month. I opened it to check for loose wire and everything looks fine.
I have always used regular AA battery and never used LiPo battery with the TX.
What could be the issue?

Another question. Does the main board take 5V power only?
I have some high quality vehicle phone charger which gives good 5V output. I can solder one inside the TX and use 11.1V LiPo battery as the TX power source.

Not exactly answering the OP, but as far as powering the TX goes I recommend a UBEC, I use one that is set to 6V and it works fantastic, use it with an 850ma 3 cell lipo, which knocks the pants off of AA batteries.

Found the culprit - a bad power switch. Short circuited the switch and the TX turned on without any issue.
I destroyed a V911 TX and farmed the switch and RF module to do the repair and RF mod. V911 TX's switch appears to have better quality than the Devo 6's switch.

Never thought of that before. Good idea and going to try it.

MatCat wrote: Not exactly answering the OP, but as far as powering the TX goes I recommend a UBEC, I use one that is set to 6V and it works fantastic, use it with an 850ma 3 cell lipo, which knocks the pants off of AA batteries.

rossyan wrote: Never thought of that before. Good idea and going to try it.

MatCat wrote: Not exactly answering the OP, but as far as powering the TX goes I recommend a UBEC, I use one that is set to 6V and it works fantastic, use it with an 850ma 3 cell lipo, which knocks the pants off of AA batteries.

Indeed a great idea - just make sure the UBEC is a Switching type and not the linear versions, otherwise you will gain little from the extra voltage of a 2s or 3s battery

The problem comes back again. I replaced the switch and TX still won't turn on. I measured the connectivity of the switch with multi-meter and it works fine. I unplugged the switch from the main board and used a screw driver to short circuit the two pins in the switch plug socket. One out of five times it will turn on the TX.
It looks like the main board is very picky about the pulse from the switch.

Is there a way to fix it?