Taigen V3 motherboard issues
 

Does anybody have any schematics on the v3 motherboard? I’m trying to incorporate it into my tank with my own receiver to control sound and other things, I hooked something up and thought I heard a “pop” but not 100% on it, didn’t smell anything burning. Now I can’t get anything to work, I took everything out, tried to get it to work with stock Taigen transmitter( it was working before I installed it). Nothing seems to work, transmitter seems to bind, I have tried multiple times, transmitter flashes then goes solid, but I can’t get any function to work on board. There isn’t any light on board, so I don’t know how to tell if board is physically bound or not. I have checks everything for continuity, nothing noticeably burnt on board, does anyone know how to check if board is bound? Also how can I trace power to possible problem? I have talked to Erik and they don’t handle any board repairs, so he couldn’t really help me there. How do I find out what’s wrong with this board!

I have a V2 unit with the symptoms you describe. I was moving the board from a PIV to another tank and it just stopped working. No damage visible. I also fried one with my Panther with 390 motors but I figured it simply overloaded the poor little FETs that have no heat sink to speak of, and it let out all the smoke. That one I sent to Erik, since it was fairly new, as a sample to give to his supplier.
I'll be watching this post with interest to see if anyone has and idea how to troubleshoot.
it looks like you'll need to purchase a new one, or move up to an independent mfr.

Jerry

I also dont understand why we cant have full schematic and troubleshooting guides with these boards. Kind of like a tech manual.
We all know when one fails, its usually a part that costs pennies, maybe a buck n half. A good soldering iron, magnifying glass, some patience and they can be repaired.
I have repaired, in the past, my clark boards and BARC boards for under $.25 in parts. Mosfets, diodes, transitors, regulators, semiconductors, ect, should all be replaceable/repairable on these boards. Just my opinion..

Enjoy,
Shad

Its mainly a safety thing. We don't want to do repairs on the boards and have floating around 2nd hand stuff. At $50 for a replacement it really isn't worth it shipping both ways and to a repair center to have it done. I save all bad, defective, or damaged boards and even transmitters and they are returned where they can be examined and taken into consideration for the next batch. I have done this since I started actually. If the factory doesn't know how the boards fail and don't have it there in front of them it is hard to improve on the next batch/revision. Unfortunately I can't really cover them when going in a custom install or different brand tank but I always try to do my best with questions. The factory doesn't provide me with any repair materials nor have I asked for it honestly. It may be a small part that needs to be repaired but I've seen MANY, MANY hobby shops burn down since I started from incorrect repairs, charging, etc. For that reason I do offer the motherboard by itself to try and keep the cost down a bit. If the customer has the know how to repair the part then please be my guest, but repairs we do not offer at this time.

I wonder if there's a business anywhere that repairs electronics boards? I have two boards for my asiatam Opel blitz that are fried, and i know it's a simple fix, but way beyond my capabilities. At $120 a pop I can't afford to keep replacing them, and one of the disadvantages to our hobby is having to deal with places in other countries, so things like language barriers can be a problem, so I would be ecstatic to find someone I could send this board to for repair. Even if it costs me $60 to get it fixed, that's still just half what a new board would cost. So here's where one of you cats jumps in and makes my day by telling me there is such a magical place, and they even have magic smoke in the bottle if they need it. ;).

Fixing a PCB without a schematic is tough. I've attempted that a few times but now with surface mount and proprietary programmed parts it very tough. I would guess there may be a common failure mode if several boards are failing in the same manner. Identifying that bad component or circuit may lead to fixing many of these failures.

Has anyone fixed a board?

If you can identify a chip or chips on the board you can look up the pin out and test to see if there is voltage by measuring between the ground pin and "VCC" or the power connection. Also check to see if there is a short between the positive and negative where the battery connects. I have also seen failures due to bad solder connections or cold solder joints. These can be hard to find, connect power and carefully flex the board, it may power up. If the board is dead you don't have anything to loose.

https://cimg4.ibsrv.net/gimg/www.rcu...7fa9b07ff0.jpg
I use this exact microscope/camera to do "micro soldering" on pcb boards.
1080p 300X zoom HDMI to a flat screen monitor. It makes it very easy to find poor solder joints and burned components.
Mosfets can be hard to see damage. Just a tiny melted dot on them can be a failure. Good lighting and a good magnifying
glass works good. As you say though, for $60 get a new one. For fun you could try and fix at a later time though...

If you have a voltmeter:
Test voltage between B+ and B- with battery connected, disconnect the battery it and measure the battery voltage, if there is a large difference in value the board is loading down the battery and there is probably a short somewhere.

Put negative probe on a GND solder pad (that's ground) then check the 4.2V, 3.3V and +5V pads for voltage.

If you have access to an oscilloscope, using GND as ground reference probe the DAT for digital signals (data) and CLK for a clock signal. Any signals or voltages will indicate if the board is somewhat operating or completely dead.

Then if one has a working board you can measure different point between the boards. That is still guess work without a schematic but it might be worth a try.

NICE! I might need one of these.

One of the IC's might have blown or failed. I had an IC that blew it's bottom out, literally. I traced the problem to that chip and when I desoldered it the bottom of it was cracked and burned, couldn't tell until I pulled it out.

The "reciever" section of the circuitry could be bad. So there should be a single signal from the antenna that is read and then all the controlled outputs are separated from that. If the board has voltages and some clock signals I would suspect the input signal is not being decoded.

Follow the input from the antenna. You would need an oscilloscope to track the signal.
At this point the only practical solution would be to have a working board and compare signals/voltages. You are probably better off getting a new board unless you are really ambitious about fixing this one.

I've known Erik for about six years now, even went down to Toledo to meet Erik and his boss at an RC show, and you're right, he's a very cool cat. One of the best customer service guys out there, and an avid tanker himself with a huge collection of very nice armor. He's also a drone pilot, probably at the semi-pro level or higher, and very knowledgeable on all things FPV. In fact, my screen name was inspired by his dog. Hmmm, I guess I might be a tad biased. ;)