Braun Shaver 7526 Circuit Board

[sigrog]

While installing 2 batteries on circuit board, board got very hot in vicinity of diode and resistor so removed batteries. Would like to try to fix by installing new resistor and diode. The resistor is surface mount R-100 and the diode is 21DQ0326. The diode is located on top of board near batteries and the resistor is under the diode on bottom of board. In the past, replaced batteries without having the hot circuit board problem. Heat is in the location of the diode and resistor. Where can I find these parts to try to repair the board? Thank you for any help you can offer. I'm an old guy with no electronics experience - just like to try to fix things.

 

[davenn]

While installing 2 batteries on circuit board, board got very hot in vicinity of diode and resistor so removed batteries

sharp and well lit photos of both sides of the board would be helpful

 

[duke37]

Seems as if you have connected the batteries the wrong way round.
If you are lucky the resistor and diode will have done their job without failure. You can test both components with a simple meter.
Does it work with the batteries connected correctly?

 

[sigrog]

I had no trouble until I installed batteries as per advice received from shaver company. When installed as directed, that's when the components failed. The resistor has actually come apart, the diode on other side of board just has dark heat marks under the diode. I thought maybe I could just try new parts and try again. Thanks for your comments.

 

[sigrog]

sharp and well lit photos of both sides of the board would be helpful

Thanks, photos attached.

 

[Tha fios agaibh]

Looks like another surface mount component went above R100 ?

 

[duke37]

Has one of the big electrolytic capacitors got a domed top?

 

[sigrog]

Has one of the big electrolytic capacitors got a domed top?

Not sure what electrolytic capacitor is, but none of the caps have a domed top - flat. Thanks.

 

[sigrog]

View attachment 33942 Looks like another surface mount component went above R100 ?

Would just replacing the diode and bad resistor solve the heat problem when batteries installed? Also, where can one purchase the parts? Thanks

 

[Tha fios agaibh]

Would just replacing the diode and bad resistor solve the heat problem when batteries installed? Also, where can one purchase the parts? Thanks

Not if a part is missing.
Did that resistor explode or did you try and solder it and it melted?
It looks like solder shorted the two traces on the right side. That could cause your overheating batteries.
There is a link to suppliers on this forum.
I'd start by removing all that solder around R100 with a solder sucker or desoldering braid. From there you can evaluate how bad the traces are.
Honestly this is probably a lot of work for an inexpensive shaver.
Have you considered growing a beard?

 

[sigrog]

Not if a part is missing.
Did that resistor explode or did you try and solder it and it melted?
It looks like solder shorted the two traces on the right side. That could cause your overheating batteries.
There is a link to suppliers on this forum.
I'd start by removing all that solder around R100 with a solder sucker or desoldering braid. From there you can evaluate how bad the traces are.
Honestly this is probably a lot of work for an inexpensive shaver.
Have you considered growing a beard?

First, thanks for responding. I did not try to solder the resistor nor did the resistor explode. I ran into this problem trying to install new batteries. As soon as I installed the batteries, the board got very hot in the area of the resistor and diode as well as the batteries getting hot. The only reason I am trying to fix the shaver is stubbornness...I know nothing about electronics, but thought if I replaced the resistor and diode, it might work and then I could try again. I don't really need the shaver, just wanted the satisfaction of knowing I could fix it. Probably better if I stuck to fixing things not quite so complex. As for beard, good thought, but wife would not be happy. Thanks again for taking time to answer...appreciate it.

 

[Tha fios agaibh]

First, thanks for responding. I did not try to solder the resistor nor did the resistor explode. I ran into this problem trying to install new batteries. As soon as I installed the batteries, the board got very hot in the area of the resistor and diode as well as the batteries getting hot. The only reason I am trying to fix the shaver is stubbornness...I know nothing about electronics, but thought if I replaced the resistor and diode, it might work and then I could try again. I don't really need the shaver, just wanted the satisfaction of knowing I could fix it. Probably better if I stuck to fixing things not quite so complex. As for beard, good thought, but wife would not be happy. Thanks again for taking time to answer...appreciate it.

Very good, I admire your stubbornness.
Something happened to that resistor to make it end up in pieces like that.
Take a close look at the blob of solder on the right side of it. It shouldn't make contact with both traces. That could be your short while the diode may still be fine. You could start by removing the exploded resistor and remove the excess solder so we can try and put Humpty back together again. The other point of confusion is what was above the resistor?

 

[sigrog]

Very good, I admire your stubbornness.
Something happened to that resistor to make it end up in pieces like that.
Take a close look at the blob of solder on the right side of it. It shouldn't make contact with both traces. That could be your short while the diode may still be fine. You could start by removing the exploded resistor and remove the excess solder so we can try and put Humpty back together again. The other point of confusion is what was above the resistor?

Thanks for the advice. I just may set this aside...if it sits long enough, I may forget all about it. I guess I'll eventually admit defeat and just let it go...thanks again for your time and suggestions. Very much appreciated.