spray the crap out of it with wd40 and let it sit a few hours. use your FINGERS to try and get it loose. repeat as needed. i will tell you from experience, if you go sticking screwdrivers in there and using pliers there's a damned good chance you will break the pin. been there and done that. every factory connector on every modern bike should come apart without use of tools. once the pin is broken you will be using tie wraps and crossing your fingers. road grime, rain, car washes, and dust all collect in there. they can be a royal pain to get apart at times. wiggle wiggle spray spray repeat repeat it will eventually come loose! good luck!
2003 VN1500 Nomad FI Bagger
2004 KLX400SR Dual Sport light adv bike
1969 CB750 K0 sand cast #1767
couple of nice GL650 Silver Wing Interstates, one with hack
2 and 4 stroke dirt bikes
other vintage stuff back in the corner