I have a router, it stopped dead out of no where. No lights, no bootloader, nothing. 12VDC IN seems shorted to ground.
I first pulled the two 470uF 25V electrolytics. On my Fluke 28, one reads 430uF and 5.6Mohm steady. Other shows no capacitance, and 9-11M ohm rising or falling slowly as probes are on it. Assuming one bad cap.
The short remains.
It looks to me (bad diagnosis incoming!!)...




that the 12VDC IN goes to R7, and also goes into an LDO circuit with a 5K/1K adjust. I don't know what this is. Unless R7 is some complicated part, I don't really see what the LDO is doing. My guess is this is a circuit to limit for overvoltage adapters, and to test this repair, I could just remove a few of these parts and wire power up after R7.
I'd love to to fix this thing, but really all I need is a temporary boot so I can get the config file from memory for a replacement.
Any ideas what I can test next?
Notes: Annoying high temp solder! Difficult to remove cleanly. Can not seem to ID many parts with the short. The gaps between positive cap and ground are small and look messy here, 99% sure those are not the short, cleaned up after photo.