Turn signal arrows stay on with headlights
 

I just changed the all the light bulbs in my '84 300D. Both tail assemblies and front turn signals. Now the turn signals stay on when the headlights are turned on. Green arrows illuminated in the dash. Either one side or both depending on how the bulbs are screwed in. The turn signal/hazard works fine when the headlights are off. It appears the bulbs are screwed in properly. I can't turn them any further. Bad turn signal sockets?

Bad grounds at the headlights.

-J

Thanks. Is there a way to correct this without buying a new harness?

Sure. The manual says the ground points for the headlights are near the headlights. Look for a wire attached to the body. Remove it, clean the connection, and put it back together :)

-J

Double check that you used the correct bulbs. If you used heavy-duty brake bulbs in place of plain old bulbs then that may cause the problem. Or if you used a combination "brake and turn signal" bulb then that may cause the problem due to having two contacts on the bulb instead of one.

The bulbs are the same shape, so it's easy to get the wrong ones.

I presume the problem didn't exist before the swap and now it does? You could also try to isolate the problem by selectively unplugging one corner at a time.

Can't thank you enough. Heavy duty bulbs were used as they weren't a problem in my old 300D. I am swapping them for standard now. See what happens.