Den64

At the risk of sounding stupid, can someone explain/help me to understand why I get a current draw from my adjustable P.S.U which is greater than 5 amps when i use the pinout from above. I take this ecu and connect it to the truck and it works fine.. so I cant understand it. I have double checked,, and yes.. the ecu is physically the same as the one in your picture,, , the circuit board matches and pin counts match. Thank you .