I have 2 exact electronic circuits, with one malfunctioning while the other is functioning. The total current consumed by the malfunctioning circuit is 0.48 A, while the functioning PCB has 0.271 A. My question is, how can I know which parts in the PCB is eating up this current difference?
What I tried so far is, to compare the resistance of the ICs in both of them to notice if there is any difference. Because:
V = IR
And so if resistance is low, current will be high. But this process is taking too long, I still have so many electronic parts to compare e.g. ICs, capacitors, transistors...etc. There are more than 300 parts in that PCB.
Is there an efficient way to find out which part to replace that is causing the high current without taking too much time?
Also: The problem isn't in powering up the PCB, it runs up just fine, but the problem is after it runs, in one of the driver ICs perhaps. I can add more details but I doubt it would be helpful.
More details
The above picture is the backside of the PCB, in the right-up, there are 2 similar driver ICs which I think might be causing the problem. They don't heat up though.