ecu box problem

Update.. I had an old black ecu in my stock pile. Installed it and the car fired rate up. So I guess my test is to leave it over night and see if it starts in morning. I have no idea what this black ecu box is from. Can I do damage to anything by running it? I noticed that my original blue box has 4 pins and this other black box has 5. The 5th is not wired up. As per installation instructions. Thanks