think I fried my Arduino

was getting ready to install a bltouch and added the 5v jumper. I wanted to test it with a multimeter and opps it shorted them out and it rebooted...

• it powers up, slower then it did before
• can't control any of the steppers (choosing move on the LCD does nothing - ( tried moving X, Y and Z )
• can read the temps (displayed on the LCD screen)
• can't read the SD card if I plug the card in the display flashes, shows card inserted but when I go to look at the contents via the LCD its empty
• if I plug it into my laptop while plugged into 12v my laptop shuts down
• if I plug it into my laptop without plugging it into 12v I can re-upload marlin
• tested with another ramps board I had as a spare and no change
• tested without lcd plugged in and attempted to connect laptop up again and no change (causes laptop to shut down)

the only constant things I have not changed are the Arduino Mega, Power Supply (shows 12v) and stepper drivers.

I ordered a replacement mega (two actually). I see no surface defects or areas where it looks like something shorted out...

am I correct in figuring that the Arduino if fried?

any way to replace on of the small smd chips and repair this one?

thanks

Edited 1 time(s). Last edit at 02/16/2016 07:35AM by buffcleb.

looking online maybe the 5v voltage regulator is fried : [www.instructables.com]

going to check the board... I do know that that end of the arudino was warm when I removed the board....

I have a 7805 in my misc parts box... so maybe?

does it sound plausible that that could be the issue... I have built lots of electronics projects but tend to follow the instructions not design circuits...

so using this image :



going from pin 1 to 2 I get 7.81v

going from pin 1 to 3 I get 11.25v

I'm using the Arduino removed from the printer without the ramps attached running on a 12v power supply that fits and is normally used for external hard drives. Directly checking the output of the cable shows 12.6v

so I am assuming I should get 5v from 1 to 2... should I get 12.6 going from 1 to 3 or is there some loss in running the board

fixed... I removed the diode from the ramps that supplies 12v to the Arduino and am powering the Arduino from the usb... first tests show everything works... can get x,y,z to go and read files from the SD card again... the power strip I use has USB out so for now I'm good to go... I have a replacement arduino on the way but I'll order replacement AMS1117 5.0 regulators as well so I have this one back in service...