Kids Ride on Toy Car Battery/Voltage

[taz24]

Hi all

I have a ride on toy car for my 2 year old daughter and the battery died after not using the car for a few months. The battery was a 12v 7ah rechargable lead acid battery.

I decided to upgrade the battery to a 12v 12ah one and having charged it up and fitted it in the car, I have lost the ability to turn the car left or right from the remote control (the remote operates via a 2.4ghz receiver). The back and forward function works fine as does the stop button and speed increase/decrease button. The battery is showing a voltage of 13.4v whereas before it was around 12.7v with the 7ah battery. The car turns fine manually from the steering wheel.

My understanding is that the increased ah on the new battery is only relevant to how long the car will last after a charge but I am now assuming this is wrong...

Could the increased ah of the new battery prevent the car from turning left or right from the remote i.e. is there too much power going into the receiver? I have attached a picture of the receiver.

One thing I would add here is that when I press the back/forward button, I can hear a signal received 'click' from the receiver unit in the car whereas there is no such sound when I press left/right so could it just be the receiver unit has malfunctioned either naturally or as a result of the increased ah? With the latter, I would have thought the whole receiver unit would have failed in this situation? This could be a red herring though as no click is heard when I press the speed buttons or the stop button. That said, could that be because these functions are within the remote itself only!

There is also of course also the possibility that the remote has broken. Is there a way I could check if it is a signal issue? I have opened the remote and all seems fine in there visually.

I will be very grateful for any help please and I apologise if this issue is too basic for this forum/thread.

Thank you all.

 

[DaveE]

I don't think it has anything to do with the larger battery. Maybe something was disturbed when you were servicing it? One thing I would do is open up the car and, with power disconnected, unplug and visually inspect each of the electrical connectors. Sometimes contacts get dirty or are misplaced, etc.

I agree it definitely might be a problem with the remote. Without an oscilloscope or some sort of receiver, I don't see an easy way to check the remote. Maybe you could see a small drop in the battery voltage with a DVM when it's transmitting?

 

[Borek]

Just drive the car forward and back till the voltage drops to 12.7V and see if anything changes (I am with @DaveE though, quite unlikely the voltage is the reason).

 

[phinds]

My understanding is that the increased ah on the new battery is only relevant to how long the car will last after a charge but I am now assuming this is wrong...

No, it is correct. AH is a measure of how much current it COULD provide not how much it is providing. Voltage is what matters but I agree w/ others that the slight increase does not seem like a likely culprit.

 

[hutchphd]

My understanding is that the increased ah on the new battery is only relevant to how long the car will last after a charge but I am now assuming this is wrong...

1. That is pretty much the only effect. The bigger (new) battery will likely produce slightly more maximum (short circuit) amps also but that is likely not relevant to this problem.. I would
2. locate the steering motor(s) and visually inspect it for the usual issues.
3. If they are standard two-wire connections, disconnct and test the lines for volts when you try the remote steering

I am assuming there is a electro-mechanical steering rig. I suppose they could do the remote steering another way: *differential power" for instance.
Most likely you will find a wire you disturbed during battery replacement. Think: did the remote steering work immediately prior?

 

[taz24]

Hi guys

Just thought I would follow up on this.

Firstly, thank you to all that replied - it is very much appreciated!

I tried the suggested ideas but all without success! I tested the two wires going to the steering motor but these showed a 0 reading no matter what buttons I pressed on the remote.

Ultimately, I purchased a new receiver and remote to try as they were relatively cheap and to my amazement (as nothing ever works first time!!), the steering has started working again. I guess we will never know if it was the remote or the receiver that was dead!

Thanks again guys.