I have a 1986 300SDL and the other day I started it up in the evening and the burned out bulb warning light came on (the little amber light next to the ABS light). I also got a little dummy buzz for about 5 seconds then it stopped but the light stayed on. I figured i had a burned out bulb and Id check it at home. There were no burned out bulbs...everything was working, reverse, turning brake, fog, everything. I started it back up again and it didnt happen this time. I let it go, then, this morning...I started it up and threw it into reverse and the buzzer came on for 2 seconds then turned off...this time, no little dash warning light. It doesnt do it often...it just started. What does it sound like, or is there a known glitch in this car?