This is what I’m looking at the back of the board doesn’t look to great but I see my original problem the top right plugin has a pin burnt off so going to solder some wires on and see what happens not sure what it might have burnt up on the board, I may have to send it to you but I would really like to replace it with something waterproof but not sure how to rewire it what would u do with the long plugin with all the pins? Thanks for the help really appreciated.
Can’t reconcile the schematic with function.
If I figure out the mistake, it shouldn’t be too hard to build a sub.
More on the board than the dc-dc converter.
Buzzer control seat belt and reverse. Eco mode and reverse mode. Converter enable.
I might have found the mistake.
Tell me what is not working.
Is it just 12v output you need?
This is how it works.
Top left is constant 48v
+48v from main coil is enable pin 7 to turn on dc-dc after delay.
Top right is 12vdc when enabled.
Contact K3 opens after delay to turn on converter.
If all you need is the 12v working. You can replace that part with an off the shelf converter with enable pin.
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I took the plugin off that was burnt off and the wires were not long enough to put straight to the board so I used 14 gauge wire and soldier it to the board it was running fine on jack stands I put it all together and set it down and it would pull about a foot and shut off sometimes blowing the fuse on the firewall I could let it set a minute and it would do the same thing do u think the 14gauge wire is not enough for the 48volt and maybe it’s not getting the proper amps to run is there a way to bypass the dc/dc just to test and make sure it’s not something else? And is there any info on the long plugin as which wire/pin does what I don’t need headlights or taillight or really anything that runs on 12volt I already have all that on a single 12volt battery I just need whatever makes the car run the basics.
Connect a separate 12v battery to the disconnected wires shown on top right of schematic.
A small agm or motor cycle battery will work. as will a full size auto battery
Use a 10amp or so fuse inline. if it blows the fuse, you will know where to look for problem.
I’m not sure we’re the disconnect wires are on the car from looking at the schematic is it something that goes to the converter under dash or somewhere else the schematic tends to confuse me I’m a handyman not to much of a tech lol
Two big wires. Most likely red and black. Look for C7 on pcb 1000uf capacitor. It is connected across the 12vdc output plug. Check for 12vdc to be sure, when it’s working.
Opposite end of the 48v input, which comes in thru the toroid coil in your picture.
Unplug and connect an external 12vdc source to that plug to feed the Gems 12v system.
A picture of that plug will help.
The only red wire is the bottom of pcb is the disconnect in any of pics I have?and what is the part circled in green called?the plugin that was broke is in 2nd pic that should be 48v in I believe do u think I might need a bigger gauge wire cause I used 14 gauge to replace the plug?
Yes that would be 48v in.
The big red is +12v out.
Near that should be -12v.
The capacitor right above red should be connected + to red and minus to ???. Big black wire or grounded to frame. Are you missing that wire? Big pin to right of red wire.
There is a small ground wire behind pcb on bottom right side so take the red and black on bottom comment them to a 12volt source that what u were saying and should I just leave the rest plugged in to pcb or disconnect them
Leave the rest plugged in.
It should not be a small black wire. Where does it go?
The screw thru board may also ground it. Poor design if it is.
I believe everything is poorly designed on this model lol at least it’s making me poor 
Should I try to use that wire as ground and connect to 12v battery or just run the hot post and leave the ground where it is
That is the actual dc-dc module.
It need not be connected at all to test.
Connect 12v to whatever these to pins where connected to.
Test converter by connecting a 12v bulb to bottom pins.
Connect 48v to top. in+ and in-
A switch from gate to 48v in- will turn on converter.
Ok sorry my phone broke had to get new one like everything else lol I finally got my 12volt working good but now I cannot get a full 48volt at the top of board hell its only showing like 5&9 volt everywhere it should be 48v even at main fuse and the car has power with the key out of it, yesterday I was charging the battery’s while on jack stands and it went crazy the throttle hung open without me around and the controller went up in smoke fried it do u think the controller could have been the problem from the start with the way it was acting or could a bad dc/dc cause this I ordered a rebuilt one but I’m scared to put it in when it gets here if there is something else wrong that caused it in first place sorry I just need some advice before I install a 500$ part. Thanks for all the help sorry but there is nobody that works on gem cars for 400+ miles from me
Do u believe a bad controller could have been what was wrong with it previously?
