What is this?

I am a bit on the new side to getting to the nitty gritty of Mopars. I finished building my engine, put it in got it all broke in it runs just fine now yet I couldnt get it to start with the key to save my life!!! then I remembered the haggard ass wiring harness I had on the plug for the neutral safety switch. I unplugged this little box-( i have no clue what the box is for or what it does) my question is WHAT IS THIS BOX???? the engine runs great with out it is it something that if its not hooked up can hurt my car in the long run? what is it for? what does it do? I nay not have even plugged it into the right place yet there is only one socket on the engine harness that matches it.

Heres a picture of the box I'm talking about the car is a 1974 Dart swinger 318 with factory AC, wasnt sure if you needed to know that but maybe it'll help.

Author: admin