I'm trying to fix my kid's power wheel. When you press the gas pedal, nothing happens. I took it apart and checked everything. I noticed that when I disconnect the wires from the motor and check them with a DVM, it registers roughly 12v when I press the gas pedal. The weird thing is when I connect the wires to the motor and check the voltage, I don't register anything when I press the gas pedal. I can't figure out what would cause that. Any ideas? Motor shot?
Two reasonable options I can think of for why you're getting zero volts when the system is hooked up:
- The battery is shot. Try probing battery voltage - a 12 volt lead-acid battery is dead if the voltage is less than about 11.8 volts. If the battery is fully charged then it should be about 12.8 volts.
- The motor is shot. Try probing motor resistance. Typically, if the motor is bad, I would expect a wire break, in which case you'd see an infinite resistance, or the insulation is damaged, shorting the wiring and you'd get zero resistance. Since you're seeing zero volts with the pedal down I would guess the motor is shorted.
If you're probing the motor, be sure you're probing it at the motor with the motor disconnected or else you're probing the entire control circuit, too, which could give false readings. The battery state of charge estimate by measuring voltage is supposed to be with the battery "rested," but it sounds like it's not working so that shouldn't be an issue.
I would guess the battery is shot, but it could also just be that it's not charged. My kids will mess with theirs while it's plugged in, so it could be someone's pulled the charger out after you plugged it in, or unplugged it from the wall outlet or turned a power strip off, etc.