DIYPNP Power Supply
 

Hi, I'd like to test my DIYPNP outside the car. I looked into buying DIYAutotune's supplied 12v power supply, but in the name of being cheap I looked elsewhere.
I found that a 12V 1A power supply can be had for much cheaper than 500ma power supplies (which is the amperage on the one that DIYAutotune sells). Would the MS be in danger of the extra .5A?
I was thinking that the PS would not supply that unless it was drawn.

You are correct the MS will only draw the current it needs. A power supply capable of providing more current shouldn't hurt the MS.

Assuming everything is working correctly, of course. Testing a board with a short on it can make a bad situation worse if you have a power supply that can deliver a massive amount of current. A 1 amp power supply will be perfectly fine. But connecting to something like a car battery or a 60 amp benchtop power supply with no fuse could easily push a repair from "replace the popped component" to "replace the whole main board".