Red Light only - won`t turn on after 1 month

[Craynerd]

I have been using a Raspberry Pi at school as a weather station using http://airpi.es/ This is a board that plugs into the GPIO ports and records weather data to Xively and Twitter @CHSweather

Two days ago, during weekend it just stopped. When I noticed it not recording data today, I found that the Pi was displaying just a red light only - indicating power but will not "turn on" or boot.

I have then TRIED a fresh SD card that I know is working in another school Pi and this also will not boot! Clearly there is an issue with the Pi. For interest sake, I then tried the SD card from the weather station in a working Pi and it will not boot.

From my simple tests, I see that both the SD card is corrupt AND the Pi is broken!

Any thoughts on what this could be? I have spent hours and hours getting the Pi to work and have not taken a backup!

I`d appreciate any thoughts. Clearly it is getting power but there is NO sign of any green light - just the faintest of a glow on the ACT light.

Any help would be massively appreciated.

Chris

[mahjongg]

read the boot sticky! is there a chance you have blown the polyfuse? even with the fuse blown, the power led will still burn, it just indicates some power, not that it gets enough power to work!

[Craynerd]

No, checked the fuse and 5.2v and 5.4v on either side.
Does it seem odd that the SD card has been corrupted as well?

Any other suggestions?

Chris

[Craynerd]

Further update - 5.3 v between TP1 and TP2.
Tried 3 different SD cards, all of which boot on other Pi and do not boot on this one.

Tried pushing down on the SD card - SD card is making contact by the looks of it.

[GTR2Fan]

Have you tried a different PSU yet? I doubt it'll make any difference, but it's just possible that it may be sticking out a 'dirty' 5.4V and upsetting the Pi.

[Craynerd]

Thank you for the reply. Yes, I`ve tried a few supplies and no luck! I`ve done lots of tests as I have a good number of working Pi`s and SD cards and definitely neither the SD card or the Pi from the problem unit is working!

What else could I have blown?

Chris

[pksato]

Check voltages of ldo regulators from TP1 to out pin.
RG2, a big one near C6, out pin is 3, above 12 label. Need to have near 3.3V. (critical)
RG1, small, near P1, above RPi logo. Its is a 1.8V regulator. (critical)
RG3, a very small between RG1 and TV-out. Its is a 2.5V.
Have a internal regulator to power main CPU, but I don't know what is a test point. (critical)
The oscillator can be tested too. But, need a good frequency counter or a oscilloscope. Or voltmeter to measure average voltage.

After some time (30min) connected to PSU, the main SoC and USB chip get hot? Are more hot/cold that a working RPi?

If all voltages are ok, oscillators working, and get a cold chips, can be some solder fault on BGA connections. Exist a way to try a repair, but It can really destroy the board if done on wrong way.

[Jessie]

Try pressing on the back of SD card (where the label is) while it boots. You could have a bad socket. It is rare but it happens.