[banaman]

After months of reading about all of your impressive creations and knowledge, I decided to convert a 12v barbie jeep to 24v ESC because my daughter hates the sudden jolt of her stock machine and doesn't ride it as much as I want.

I bought a YK31C ESC, wired everything up, jumped the on/off switch connector, pushed on the throttle, and then nothing happened. I'm getting 0v from the "motor" connector whether I press on the throttle or not. Two 12v 10Ah batteries are fully charged and pushing 26-27v, and I have ~24v on the "indicator light" connector and 4.5v on the "throttle" connector. The throttle pedal signal wire (white) goes from 0.8v to 3.3v when depressed. Brake switch, brake light, and charging cables are not connected to anything. I have also verified the motors work when connected directly to a 12v battery.

Is the ESC bad or do I have something wrong? Should the throttle be going all the way to 4.5v?

[toycrusher]

How are you checking motor output volts? I would check motor output positive to battery ground for 24v. The + side is direct inside the ESC so if you don't have that then a wire is broken. The ESC "pulses" the ground connection to provide speed control.

If I was guessing I would say to swap around throttle connections. Sometimes colors don't match.

[banaman]

Thank you Mr. Crusher. I was looking over some of the schematics on this forum for wiring the ESC with reverse and brake. Can you tell me why the 100 Ohm resistor on the 24v indicator line is needed? I imagine the relays it is connected to can handle the voltage and current.

[MR_Pat]

Some relays are set up for 12v trigger.. that resistor knocks down the voltage to 12 v so anything you might want to run 12V off of is there for you.. and i think switches will live longer on 12v vs 24v. but thats just my thought.

[toycrusher]

Yes the resistor lowers voltage. I personally haven't used them and though I've burned up many things it's never been the coil side of relays

[MR_Pat]

in all fairness i haven't used that part of the esc kit yet. as the harness i got was from a scooter that had a dash and headlights and turn signals and already had a 12v stepdown built in. I dropped the entire harness right into the car and went with it .. added the relays and kept the 12v i had in the front of the vette to act as the trigger power source for the relays. and then the 2 12v for the esc under the seats