Razor E100 Scooter Troubleshooting and repair
Hopefully, the steps in this post will help you identify and fix your problem.
The most common problem with Razor electric scooters is dead or dying batteries. The second would be the controller box and the third would be broken wires. Hopefully, the steps in this article will help you identify your problem. Also I filmed all process on video and it will be available soon on my youtube channel. So to do the testing you will need a multimeter. If you don’t have one I provide links at the end of this post. So you can order it at Amazon.
Power adapter test
Before we test scooter let test charger, plug it in and We are just going to be testing it on DC voltage.
Measure voltage between sockets 1 & 3 it should be about 27 - 28 volts without load, mine showing 28.3 volts. 
If output is zero or less than 24 volts your charger is dead. Use this link to get a replacement.
By the way you might also want to wiggle this around while you're testing it just to see if it fluctuates here if it does you could have a kink inside or a broken wire inside something like that that's stopping it from charging the batteries.
Disassemble deck cover
To access internals you need to disassemble deck cover it secured with 6 screws, so use phillips screwdriver and unscrew it. Then remove cover.
Battery test
After cover is opened, disconnect batteries from the controller, and measure output voltage for each battery, it shoud be about 12 volts or more. Mine batteries show 0.8 and 1.9 volts so this is values of dead batteries. So if your battery is dead you have two options try to restore it or buy a new ones. 
Battery repair
I decided to repair battery. To to this open it't top plastic cover first. 
Then remove rubber cups, my butter has 6 caps. 
After that refill battery with distilled water. I use straw to to this. 
Connect battery to Car Battery Charger and select recovery/maintenance mode. At the start battery can't accept charge so keep it on this mode until it starts accepting charge. I keep it about 20 hours to be restored. 
After 20 hours battery ready to be used. Put rubber caps back and the put top plastic cover on place. I use scotch to keep it in place. 
Throttle test
The throttle has two switches inside one that hooks up with the orange wires the other one that hooks up too with the brown wires. So we're going to take our meter and then shove these leads in matching sides. So shove them there in the orange side, meter should be in continuity mode. Then just pull the throttle and your should hear beep so we know that switch is good. There's another one in there so we're going to test the brown the same way. If you didn't hear a beep you will need a new throttle. 
Brake test
The other wires coming out of the front are the brake wires and this is an easy test because it should be without you hitting the brake so I can get these leads in you'll hear the beep okay and when you pull the brake lever it'll stop
Also near brake handle there's a little switch and you should hear a click when you pull the brake usually when you hear a click it means the switch is good.
Motor test
Motor will have a certain amount of resistance and I don't know what a brand new motor will test that but I know this one works so this will give you a really good idea of the resistance of a working motor see this big thick wire this one goes straight through the back to the motor. Mine motor resistane is 6.3 omhs. 
Reset switch
Little thing with button on the side is a safety trip in case the voltage surges. If you use meter on it it should be continuity all the time. If meter not beeping try press a little button on the front so you can reset it. So if you don't hear a beep then that might be a problem with it.
Power button test
When you turn it on it should be continuity between bottom two leads.
Controller test
To test controller be sure first that all other parts ok. It should be at least good battery and working throttle, wire harness, power button. THen pull the throttle and your should hear a click sound inside controller. If you don't heard it, probably relays inside controller is dead. If you don't have special skills, just replace the whole controller.
Tools used in this build:
Replacement parts
I'm working on an E100 but these parts may also work on Razor Power Core E100, E125, E150, and other scooters. Just check the part numbers.
- Razor Electric Scooter Battery Charger
- Replacement Controller W13111612015
- Throttle
- Razor 20A Reset Switch W151250011112
- Power switch
- Reset switch
- Electric Motor for Razor E100/E125/E150
Also check your Razor E100 version number as I shown before.
Find out E100 wiring diagram on the picture below 
Best of luck with your repair!