My courtesy lights would not come on with either door open. But the security light blinked properly for both doors. Courtesy lights DO come on with manual switch. So I replaced the relay and BAM, courtesy lights worked perfectly. Now they stopped working again. I pulled the fuse...it was not blown...I put same fuse back in and BAM, courtesy lights working again. Now they won't come on, fuse pull didn't work, relay is clicking as it should, both door switches are seemingly working since security light flashes. Is it still possible that one of the door switches is causing this? Any idears out there? Thanks in advance!

Could be a problem with the timer module. Do the lights stay on when you close the door, and then turn off automatically after a minute or so?

If the lights are working, they work to perfection. The timer is right on with everything. When they are not working, I can still hear the relay clicking with the correct timing. I am so stumped it's ridiculous. Any other ideas? I just replaced both door switches for no reason. There is no ryme or reason to them working or not working. But manually turning them on always works.

Remember the first law of Corvette electrical work - check all your grounds! Sounds like corrosion on some of the contacts, that would explain worsts sometimes and doesn’t other times!

I put LEDs in the door lights on my ‘89 and now they stay on all the time. I’m going to open them up and see if I goofed up the switches or if it’s the relay, or if I need resistors in the circuit.