M.L. Toys
M.L. Toys
HobbyMasters M.L. Toys
Need new batteries? Going from 12V to 18V or 6V to 12V? Wiring Questions?
I have a stock Boss Mustang that stopped working recently. I'm thinking it's because my son washed it on the inside and water got into some of the components.

When I push the gas pedal down, nothing happens. Thinking it was the switch below the gas pedal, I ordered a new one and installed it. Unfortunately it's not making a difference.

I measured the voltage on the plug (connector 1, 2 and 3 - picture attached) and when the gas pedal was not engaged all connectors showed 11.2v. When I pushed down the gas pedal it showed the following:
Connector 1 and 3: 0.23v
Connector 2 and 3: 0.15v

I also measured the voltage on the motors by the rear wheels and both motors showed 0.3v when the pedal was engaged.

I'm not skilled in troubleshooting electricity, but it seems like the problem stems from the switch and not enough voltage is passed through to the motors. It's just strange that both my old and new one wouldn't work?

I'm hoping you guys might be able to give me some ideas of what I could try next?


Thank you for your reply!

I managed to get the charge up to 12.9v, but the motor is still not engaging. Do you think it's still the battery with a 12.9v charge?

If so, I'll go ahead and order a new one (I saw you have them for sale too), but I just wanted to double check, so I don't order a new one and it being something else.
Does that model have a variable speed controller?

Easiest way to test the battery is to measure the voltage on it while you apply a load (if installed in the vehicle and you're confident in the wiring, just pressing the foot pedal will do it...) A very bad cell will cause the battery to go to near-zero when a load is applied. If it doesn't change at all, then you've got a problem downstream. If you have access to any other battery (even something like a 9V drill battery), you can use that to check as well. if it runs on the other battery but not on the stocker, then clearly that's a battery problem.

Also -- my experience is that usually if a battery sits for a long time at low voltage (like 11.2), it will have gone bad. They need to be kept in a charged state, every 3-6 months if not in use.
BINGO! It's the battery.

I really appreciate your detailed suggestions on what to do to troubleshoot the battery and make sure that was the culprit. I didn't think of using a drill battery to test, but I found an 18v, wired it up and the car fired right up.

I tried to maintain this battery by not leaving it in the car after use, storing it in a cool place, always charging it after use, etc., but apparently I still failed on that accord :roll:.

I'll order a new battery from M.L. Toys since he was also helpful. Thanks guys!
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