I’ve been working on my 99 D1 project car for a while now. Got it out of park by replacing the brake light switch, however the brake lights still do not work. The one above the spare works just fine, but the rest do not come on. I have replaced all the bulbs. Walked out one day and noticed that the previously working turn signals don’t come on either. Been struggling for weeks now, can anyone help?

 

take a good look at the sockets and see if they are melted. then check the tail light assembly contacts for corrosion. easy to get to and easy to check.

 

Sometimes the socket gets hot due to heat build up from the brake light being lit for prolong periods of time ex. traffic. My son's D1 had the issue where he replaced the sockets twice and in about 6 mths to a year intermittent failure he would then need to replace it again. After checking it we found that the socket wasn't making good contact with the tail light assembly so we cleaned the contacts on the tail light assembly and the socket then added a toothpick to wedge the contact to protrude more and make a solid contact with the tail light assembly then applied epoxy in between to support the gap created by the toothpick now no more intermittent light issues.