I have a problem with the daytime running lights on my '91 740. They won't shut off at all. Back story: When I first bought it, several times I accidentally shoved a house key in the ignition before finally removing the nearly identical key off the key ring. The tumblers were a bit disturbed and sometimes I had to manually turn the key back to get the starter to retract. So, I sprayed some lubricant in the key slot and proceeded to work the key back and forth, only to find that the lights would no longer shut off at all. Had to disconnect the battery to get them to quit. I then replaced the relay for the running lights, but there was no change. I found that if I left the relay out, I had normal lights (though no brights) if I turned the headlight switch to the "parking light" position. That was over a year ago and I believe the ignition switch has settled back to normal, but haven't yet been brave enough to reinstall the relay and see if all is well. Could it be that the ignition switch needs to be replaced? Or does anyone have other possibilities?

 

that ignition switch provides switched power to things including the headlight relay(s)

most likely the issue

also on locks use dry graphite lubricant (you can get it at the key section of home depot) the liquid kinds collect dirt and cause the mechanism to jam over time

 

Thanks for the response and verification, Nichals! I appreciate it!