Hi everyone!

I have a RC car transmitter, an Absima CR3P, that a few days ago, decided not to turn on anymore.

When I power it from the bench PSU, no current is passing. Voltage "gets" to the PCB when I press the momentary switch push button.

I'm an electronics noob, but I attach pictures of what I think are the voltages on the regulators (picture is marked with "EDIT" at the end of the name) and relevant info on the PCB.

Thanks for any help provided in advance.

 

Welcome to AAC.

Your best bet is to use the signal tracing method of troubleshooting.

First, turn on the current limiting of your bench supply and keep it down to about 100mA. This is a safety measure so if there is something that wants to burn up you won't supply it with enough current to let out the magic smoke.

Next, start with the input to the board from the supply where you can measure the voltage. Then trace the path from that input to the next component the positive side encounters and see if the the voltage is present on the other side of it. If not, the component is bad, and may be a protection device.

Replace that component then with the current limiting fully down slowly turn it up until there is some current draw indicated, stop at that point then repeat the signal tracing step. If you find a component that stops the signal, try turning the current limiting up very slowly to see if that component appears to get warm. If it does, it is probably bad since the input voltage doesn't get past it.

You can try turning the current limiting up slowly not exceeding the expected draw of the device to see if the voltage was insufficient to allow the device to supply anything. The device might get noticeably hot as you do this. If it does, and an amp or so of current doesn't get the voltage past it, replace it and repeat the above.

The current limiting is important because if the first device is protection of some sort it is unlikely to be the cause of the problem, rather it will be a victim of it. Once that is replaced, applying full power is very likely to simply fry it again. Keeping the current down will help prevent that.

If your supply doesn't have current limiting you can slowly turn up the voltage which will do the same thing.

 

The other choice, both are good, is a close inspection with good light to see is a soldered connection has broken. The "Y" method will find that but a visual may be faster.

 

Thanks for the answers.

At another forum, a pretty nice guy helped me find the issue. It was a 0.62€ voltage regulator.

Everything is working fine now.

Have a good one!

 

The other choice, both are good, is a close inspection with good light to see is a soldered connection has broken. The "Y" method will find that but a visual may be faster.

Thanks, @MisterBill2. I neglected to mention visual inspection which is always the first step both for effective troubleshooting and for safety.