I have tryed everything I can think of to solve my issue on this.
It will reset randomly when eoc-ing and shutting off car when parking. I have checked voltage. 4.98v on the output of 7805. Checked all connections solder joints good, car connections are soldered as well.
I have installed a second 12v 2ah battery under dash, which is connected to vehicle with current limiting resistor(600 mah) and a diode. The resistor is so I don't fry the 2ah battery by charging too fast, it also limits voltage to 11.5v going to the guino's 7805.
The last time it reset I had about 140 miles on tank, was going to put some gas in tommorow to get a rough setting on gallon usage. But the guino decided to reset so I have to start all over again.
I have also added a 470uf in parallel with the 330uf cap on output of 7805. I don't know what else to do.
I have noticed the lockup issue I was having has not happened since adding the extra cap and backup battery. And this issue was happening more when hotter out, the guino is out of case right now for diagnosis and nothing has even felt slightly warm to touch.
I am lost please help. Ran out of ideas, other than maybe backlight on lcd maybe?
