I was using my pi as a wifi router using USB wifi adapters and saw "USB over-current messages".

I removed the USB devices and over-current messages stopped. however after some time. Pi restarted and doesn't boot now.

The Red LED doesn't glow (changed Power supplies, tried powering up using GPIO header).

The green LED is glows continuously (no blinks, solid).

SD card looks fine, no corruption (i mounted in my laptop and was able to read the files)

The Middle chip at bottom gets hot, if i leave the pi connected to power. I waited for 24hrs as some websites suggested that fuse may have gone bad. But still it is not booting :'(

LED Picture

  • The pi does have various polyfuses. I'm not promising one is involved, but you could cross your fingers and leave it unplugged for a day or so. Someone else here reported similar symptoms recently, BTW, at least WRT the red LED being out and it not booting.
    – goldilocks
    Oct 15, 2015 at 12:42
  • @goldilocks i already waited for 24hrs, no luck. any rework can be done ? how do i isolate to confirm if polyfuse has gone bad ?
    – raptor
    Oct 15, 2015 at 12:53
  • I have no idea, that was just a hail mary thought. I don't think they should take that long to come back.
    – goldilocks
    Oct 15, 2015 at 12:54
  • If you have a multimeter you could do some probing on the board to check various points such as voltage regulator outputs
    – Jodes
    Oct 26, 2016 at 2:17

3 Answers 3


Remove everything. Plug in a freshly-burned SD card. Plug in a known good power source (maybe a branded phone charger, about 1A to 2A current, Samsung charger maybe)

If the RED LED flashes, it should mean that it can still boot. If not, maybe the LAN chip got fried (Symptoms: hot chip).

Grab a voltage meter. Power up the pi using the power supply. Look at the reverse side of the pi. Check these points (These are from memory. It may be wrong):

PP1, PP2 and PP7: Should give out 5V
PP8: Should give out 3.3V
PP9: Should give out 1.8V

If everything is good, your LAN chip may really be fried. If not, try to find a way to fix it (Take note that the Pi may become a fire hazard).

Safety first. If you smell smoke, remove and decommission the pi and get a new one.


Plug out all your USBs, energy, HDMI, SD card and everything!

Take Raspberry Pi get out from the case.

Clean your Raspberry Pi's top and down sides centle with soft brush.

Only put HDMI and energy cable with micro SD card.

Start your Raspberry Pi.


I would also add heatsinks to the Broadcom chip and the ethernet chip (the two chips on the board.) You can find them on Amazon and the like.

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