I have a 90 DX Civic. Problem with the signal/brake system. The signals appear to work by themselves. The left in the other hand shuts off when I apply the brake. When the left is on I can see the shift interlock engaging and disengaging in unison with the signal. When I turn on the headlights, the left signal does not operate. I have read a few things about a ground issue but the connection with the shift interlock is what is confusing me. Any ideas?

 

sounds like your turn signal lever is just broken

 

Im pretty sure the lever is working since it operates left and right. The right signal works as it should. Further investigation of removing the bulbs, I noticed that all of the left rear lights flash with the signal and all pause when brake us applied. On the dash the left signal is solid when the brake is applied. Im thinking a wire is crossed, where I am not sure. The shift interlocking should only be engaging when the brake is applied but with the left signal on it opens and closes. If anybody has a wiring diagram of the brake and signal assembly that would be great. Im thinking of investing in a Haynes sooner than later.