One of my subscribers is trying to repair his Cisco ASA5505 firewall: https://www.youtube.com/watch?v=0sHLUDITr6A
As I understood from his video, he has a power issue, where the ASA5505 is not turning on, but after replacing the chopper transformer if he heats up the area around the transformer with a heatgun, the firewall starts up.
In such cases 80-90% of the time the issue is related to the capacitors (mainly electrolytic and tantalum caps on this PCB) which have high equivalent series resistance when they are cold due to old age, since the electrolyte degrades with time.
Thus, the highest chance to fix this ASA firewall would be to replace the three electrolytic caps (these are the yellow caps on my board, but they might be also black, gray or even purple/red on yours). Furthermore, the two electrolytic caps should be also replaced. Since the tantalum caps tend to be expensive, one can bodge in electrolytic caps in their place as well.
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