Well, certainly wasn't planning on posting again tonight...

So, this week, I learned that my rear driver's side turn signal wasn't working. Turns out, it was just a burnt out bulb so I swapped it out today and it worked. I swapped the passenger side too BUT when I was pulling that bulb out, the glass part actually unscrewed from the base. I had to get pliers to pull the base out of the connector and then pushed the new bulb in. I tested the blinkers by turning the key to the 'on' position (before ignition) and then switching the turn signal handle to each side. Everything checked out fine so I went about my day.

Tonight, I was driving and noticed that NOW the damn passenger side blinker wasn't working! It worked when the headlights were off - or even just the '1st' pull setting of the lights **** - but when the lights were on, nothing. What is this?! I've never seen this before and have no idea where to begin. Fuse? The passenger blinker was working fine this past week when driving at night so I'm really, really confused here. Any ideas you can come up with will be very much appreciated.

 

Did you replace it with the correct bulb? A single filament bulb where a dual filament bulb should go could do this. Also a bad ground could cause this.

 

Bad ground, or worn out socket. I'd check also to make sure you've got the lamp in correctly. They wont go but one way when the socket is good, but I've seen old worn out sockets that allow a lamp to go in 180 degrees off. Move the lamp to the other side and see if it works there. That will eliminate a lamp issue. Look at the socket and make sure it's clean and in good shape, and check the wiring.

 

It was definitely the proper bulb. They matched when I pulled the old ones out and the driver's side new bulb works without a hitch. I think something got screwed up when I had to yank the old passenger side bulb out. The light itself turns on but the blinker part is what isn't working when the headlights are on. Confusing!

 

I'm going to give that a try and swap the bulbs this morning. The socket, from what I remember, is in good shape and wasn't really beat up or anything. And, bulb itself does blink when the headlights are off but once I turn them on, it doesn't work. It's a confusing, annoying thing. Should've just left the old bulb in there! haha

 

Jesus H Christ... I pulled the passenger bulb out, rotated it, stuck it back in, and just made sure it was tight - magic, it's all working as expected. Thanks everyone!

 

Happens all the time when bulb is in backwards - different position of the keys on the base are suppose to prevent installing backwards, but the socket enlarges itself and this event can happen. Common problem.
Good you found it.

With the bulb backwards, the lighter (tail light) filament is in the circuit and the whole circuit, the right side bulbs, and cluster indicator, do not present enough load on the flasher, P/N 512, and t/signals never flash.

 

Yep, I've seen it happen often! Sockets look good, but just enough wear to allow the lamp to go in 180 degrees off, and contacts don't quite line up well. Glad you got a simple fix!