Mamba Max repair

[Sammus]

Alright, so I've pulled apart my MM a few times now. Initially to modify it, then to repair and test it. Still having no luck though, and refusing to cop out and send it off to Artur or Castle to have it done properly, I'm resorting to ask for help (in several different places...)

I'm pretty sure I broke a few of the solder rings when I initially separated the control board and the FET board, there were 3 that I'd obviously broken, and subsequently repaired (16,17,18 in my incomplete diagram) so I decided to check them all. I got all the easy ones, and a couple of the less easy ones. I still can't manage to find alternate points for the pins I labeled 11-15 and 19.

I don't suppose anyone else has done this and can help?

And before it gets suggested, yes I have PMed Artur just thought I'd throw it out there and get any other suggestions too.

Cheers

Sam

[DrKnow65]

Some of the solder rings (buss pins) are not used (I'll check the extra MM I have apart again because I fixed it once and had installed a bad part!?!?!?!).

Glad to see you are doing the "pin out" for the MM I've got a good layout for the power board but havn't put it to pic's yet (like your brain board) I'll try to put some time into it today to help identify which pins are what...

Some of the stuff I can tell you is that the power board is 4 layers (top you can see, positive plate layer inside, negative plate layer inside, and bottom you can see).

The brain board is only 3 (top, middle, and bottom).

You can see through the brain board with a good bright small flashlight.

The brain board on the unit I'm repairing was damaged pretty bad when it was disassembled for mods (before I got it) so I've got to do some ring/trace repair as well. I also have had to carefully drill down to the positive and negative plates where the cap's attach in the power board as their rings were pulled out too.

I'm not an electrical engineer (genius) like Artur, but I would like a good understanding of the unit anyhow...

I would like to repair the spare MM but I fear the brain board may be too damaged already. If I can't get it done I'll propably hit Artur up for a new brain (going to see the wizard...) or use it to do the stage 2 mod to my modded MM. We'll see.

[DrKnow65]

11, 12, & 15 are not used. Not sure about 13 & 14, have to do some cleaning to see better...

If I don't use this brain board I'll pull the components and sand it down to the center layer and get a proper schematic of the whole PCB. Would like to do that with the power board as well but it's too valuable and still in decent shape.

[DrKnow65]

Should wait to hear from Artur but it sure looks to me like 11-15 are not used...

EDIT: 19 is not used either so far as I can tell.

[Sammus]

Hmm I wonder why my MM isn't working when I put it together then? Nothing looks damaged... every other pin is connected to the brain via something. The FET board looks completely undamaged...

Is there anything else obvious you know I could check? If I hook it all up, I get power through the BEC into the Rx, and CastleLink recognizes it fine and I can program it etc. But with the motor plugged in I get no tones or anything, and just two red lights on the esc... Hmm...

[DrKnow65]

Brushed mode? LVC too low?

On a bench, just hooked up to a battery you should get red/green flashing.

Try updating the firmware (you can do this even when it still has current firmware on it).

Can you program it to the transmitter? i.e. full throttle, plug it in, ect, ect ect...

[smokyracing]

how did you get the heat sink off ?? thanks

[Sammus]

Hit it with a heat gun for a bit and it just falls off. Advice courtesy of Artur.

[Sammus]

Just got home, resoldered it all together and no matter what I do, I just get 2 red leds on constantly. I tried re updating the firmware, disabling the LVC. Didn't bother trying to hook it up to the rx etc...no red/green so I think its dead :(

[Sammus]

Alright so this is all I get when I plug in batteries. Now they both look red to me, I am colourblind though so it could be something else. It's a bit hard to see in the photo I'll see if I can get a better one...

Second, is that third (top) little pad meant to be an LED too? The manual mentions 'All' as opposed to 'both' LEDs going one when programming is successful. Either way, there doesn't seem to be one there... maybe it fell off with all the heat of desoldering the original hookup wires. Surely if that is meant to be an LED it wouldn't affect the main functionality of the unit?

[smokyracing]

what epoxy should I use to re glue it on should I use a high temp one or ? thanks

[Sammus]

Make sure you separate the boards and remove the caps before hitting with the heat gun - I dunno how good direct heat would be for those capacitors.

To put it back on you'd be best off using some thermal transfer compound like what they use to attach heatsinks on pc's. Note there is a normal kinda goo stuff that says soft (bad for this application) or an epoxy version. You want the epoxy. Also you can get silver based versions and ceramic based versions. Probably best off to stick with the ceramic - as the silver one has a bit of capacitance which isnt great if you get it on the circuit board.

[DrKnow65]

Use Arctic Alumina, you can get it on ebay or a good electronics store.

You have the yellow and red led's lit Sammus, the green is the one you are missing. It could very well affect the opperation. Artur may have one from a stage 2 conversion he's done as they get removed from the second power board.

[Sammus]

Could I just short it out? :P I might just whack another LED in its place and see if it works...

[GriffinRU]

• Check Power at node 20 should be Battery voltage
• Check 5V at pin 8 of SO-8 chip on the same side with MCU, node 20 is pin 1 of the same chip.
• Check 10V at pin 1 of SO4A (small 6pin IC)
• Check 10V at pin 1 of SO-8 FET drivers
• Check all diodes, 3 pin IC's
• Remove excessive heatsink compound from MCU pins

Let us know, results

And, yes I have spare MM-brains boards. They are very reliable and easy to fix. Although haven't drawn schematic yet.

See attached zipfile for FET's schematic...