xmod evo bumblebee help

[RootBreaker]

Ok so not sure if you saw my other thread - think it is in the wrong section so if a Mod sees this please move it to here...

anyway.. I got 1 losi micro t and 3 xmods.
I made sure we tested each one to make sure they all worked and they did.
I just went to test them in the garage with fresh batteries. Cop car and dodge worked great... Bumblebee on the other hand doesnt want to work.

I put batteries in it 4 in the bottom and he modded it to take 2 more up on top.

when I turn the power of the car on the headlights flick on then off and dont come back on. I tried other batteries, put those batteries into a different car.
nothing..

I took it apart somewhat and not sure what im looking at. Any help is appreciated on what to look for or to check or test.

on xmods forum someone posted no power but steering works. Mine does nothing.. no steering and no motor control.

 

[RootBreaker]

ok so i saw something wet under the car on my bench so tore it all apart...
ended up being solder flux when original owner soldered a wire in to extend to add a 2 cell AAA holder making it hold 6 AAA...

took esc out and flipped it and wiped up all the mess... so now here is something I did note..

if I take one of the others and leave the TX off and power on the car it does the same thing. lights on that car come on real quick and turn off.. kind of like the tx and rx are not syncing....

so for now I swapped the entire rear end from bumblebee with stage 2 motor to the cop car....

 

[cycleguy]

If there's enough flux dripping off to notice then id say your problems in the electronics hack.Do you know what a cold solder joint looks like?go through his work and look for hairline cracks in all of the solder joints.

What kind of receiver and transmitter are you using?I'm working on a buggy upgrade, one of the rc techs at Banggood helped me get a proper receiver and esc to upgrade it so I can run all my rc's off of my 7.4v lipos.If you are trying to get bye with components you aren't sure of then you might just want to take the plunge and upgrade that stuff.I bought the nicer digital Flysky Gt3c transmitter and it wasn't much more then buying one Iosi rx/esc.Now that my Gt3c is paid for I'm only looking at $8 for a rx and $10 for a esc when I need it.I'm still fairly new to this stuff and I'm having trouble identifying motor sizes and power consumption, but the rc guy at banggood told me its better to use a larger esc if I'm not sure.So I went ahead and bought a few esc's to try out, 10a-30a miniz esc's for my micros and a larger hsp esc for my boat since I know it has a 300+ sized motor.It sounds like I spent alot but I only spent the price of a Trail Trekker and I even had enough left over to pick up one of the new 1:24 Hsp crawlers and some materials like Jst connectors.

 

[RootBreaker]

i will have a look at the cold solder joint as a possibility. I did txt the guy and he said he had it do this a few times and said for me to go to youtube and see how to switch the esc wires. He said that maybe it.. but to me that dont seem right. It drove when i bought it from him so it does run. Has to be either a bad board or cold solder joint.

I am using the stock setup as in rx and tx.... it is channel 12. it sucks that it does not have removable crystals, well at least not in the controller or I would have swapped it out with another to have a test if it is the tx....

do you or anyone you know have electronics they pulled that would work? a channel 12 board would be nice..

I want to keep it stock as this is going to be for us to play in the house... I put some rechargable aaa batteries (only 800mah) into the cop car and wow it drives so nice... well after I put the stage 2 motor from the one that is broke. Why not i figured....
so fast enough for us for indoor use...