[SOLVED] Electrical contact failure

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Mitteau
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[SOLVED] Electrical contact failure

Post by Mitteau »

Hello everybody,
My crazyflie2 works hard since I bought it in November 2015.
Probably due to many crashes, the M3 blue led has random functioning...
What is strange, when I push with a pencil in a fixed place of the breadboard, the led is right controlled.
Here you can see photos.
How can I repair my copter ?
Thank you!
Jean-Claude
Attachments
SAM_1241A.JPG
SAM_1239A.JPG
Last edited by Mitteau on Sat Nov 11, 2017 9:42 am, edited 1 time in total.
tobias
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Re: Electrical contact failure

Post by tobias »

I would expect the track to have a crack somewhere and highest probability for that would be closest to the led pads. I would scrape off the solder resist just beside the pad on the track and solder it together with the pad.
Mitteau
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Re: Electrical contact failure

Post by Mitteau »

Hi
I have a new machine for a few months. Now, the bad contact is for th M4 (transmission) LED. I will not try to repair because I lost one machine with wrong soldering attempt...
tobias
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Re: Electrical contact failure

Post by tobias »

Could you take a makro photo of the M4 LED. Maybe we can spot the problem and hopefully there is an easy fix?
Mitteau
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Re: Electrical contact failure

Post by Mitteau »

Hi Tobias
The quad is connected.
When I push up the M4 arm, the M4 led is off.
When I push down, the led blinks red/green, which is the right behaviour.
See photos.
SAM_3250_r.JPG
SAM_3251_r.JPG
SAM_3252_r.JPG
On the third photo, the LED is OK.
I don't think that there is a solution. Nothing is visible on the PCM.
Jean-Claude
tobias
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Re: Electrical contact failure

Post by tobias »

Then I don't suspect that the trace has actually cracked but that the solder to the LED is to blame. I think it should be fixable by quickly just melting the solder on each pad of the LED.
Mitteau
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Re: Electrical contact failure

Post by Mitteau »

I'll try...
Mitteau
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[CAN'T BE SOLVED] Re: Electrical contact failure

Post by Mitteau »

Hi
Impossible to repair when the cracks are in the track which is the case here.
marcus
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Re: [CAN'T BE SOLVED] Electrical contact failure

Post by marcus »

Sorry to hear that you weren't able to fix it. If you have Flux try adding a bit of that while melting the soldering, this will make the solder creep better.
Mitteau
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Re: [SOLVED] Electrical contact failure

Post by Mitteau »

Hi
I changed the status from CAN'T BE SOLVED] to SOLVED because the discussion is closed now for me. But the problem is still present, my boards are really high sensitive to shocks.
A+
Jean-Claude
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