ok heres my situation.. I have a used AEM EMS on the way and I would like to be able to connect to the ecu to check it. My car is currently apart and has no motor, wiring, etc. The seller states the ecu is in perfect working order but I like to double check just because...

Now, the dilemma... I have a complete engine harness out of the car that I can plug up to the aem and power with one of my numerous batteries I have laying around... What do I have to power to be able to read/write?

Power Source 1 (+12v switched)
Power Source 2 (+12v switched)
Voltage Back up (Permanent +12v)
Or will the ems read/write with just the battery connected since the Voltage Backup should already be powered?

I searched with absolutely no luck. I dont care that the ecu won't read any sensor values.. I just want to make sure everything is in working order

Thanks

 

Remembered I could call AEM

Here's what to do if you want to connect to and read/write to your ecu without a harness or it being in a car

all you have to do is give 12v power to one of the 12v switched power inputs and a ground to the main ground pin and you can connect and read/write without using an engine harness.