89 K-1500 weird electrical problem

[stewart14]

I've got a1989 K-1500 & it just developed a problem with headlight/parking light & dome light. None of these work except when i use the remote start (aftermarket which has been in for 10 years). As soon as I shut the truck off with the remote, the lights won't work. I figured it might be a problem with the remote unit so I unplugged it & still no lights. I checked at the fuse box & light switch & the only time there is current is when I use the remote. I've worked on a lot of vehicles over the years, but I'd have to say this is one of the weirdest problems I've run into. I was hoping somebody might have an idea??   Thanks & for now I think I'll have a beer!