87 300zx my foot step lights stay on and left door step light does not work, dome light on the roof works from both doors also the ajar light works from both doors. when i unplug the light control unit the right door works like it should but nothing works from left door when the unit is unplugged. this problem has me all confused any help would be appreciated thank you

 

Sounds like the door switch is hanging up. Try pushing it in when the door is open to see if the lights go out. If not, it may be corroded & needing replaced. Don't forget, I believe there is a delay switch on the system as well that slowly turns off the interior lights when entering & exiting also. My 85 has this.

 

I beleive it has a ECU time unit for the lower lites / alarm

sounds like his door swt. is working
check the schematics