Once this problem occurs, it most likely indicates a weak battery and re-seting the switch is useless. If the unit still does not work after recharging, you need to do a battery test.

Do a Battery Test

Battery voltage test: A fully charged battery should be at least 12 volts or above. With only 7 or 8 volts on the battery, the sound box may work but the car would not be able to move. If you have charged your battery 14 hours, and the battery is only 7 or 8 volts, your battery needs to be replaced.

Please bring your battery to the nearest shop (such as electrical car shop, auto zone, or radio shack) to find out the actual voltage on the battery if you don’t have a voltage meter or multi-meter to test your battery. Testing battery is very simple and easy, it won’t even take a second and you don’t have to pay anything to test your battery.

Charger test: Also, have your charger tested as well by plugging the charger to power outlet and measure the output voltage and current on the charger.

If battery is no good, you need to replace a battery. Click here for detail

If the battery is good, you may have a bad on-off switch.

Do a on-off switch test