Hi guys, I'm new here and I have a 2007 Aura XR (106,000 Miles) that is having some turn signal issues. The front right turn signal is not flashing but the back right one is (left flasher works perfectly). I've tested the bulb and it's all good. The small light bulb on the left quarter panel is not lighting up either so I believe they are connected.

Any suggestions? It's done this since I got the car. I didn't see any fuses/relays marked "turn signal" in any of the three fuse boxes. Wires seem to all be ok as well but I'm not a professional. Any help is appreciated.

 

Are you seeing voltage at the bulb sockets in question (betw bottom center and side ground)?

 

I tested both sides and only one side is getting voltage. The socket does not appear to be melted either. Do you know if the wires that go to the light bulb are directly connected to the turn signal switch on the steering wheel? I'm trying to figure out where the wire goes because I think it's a wiring problem.

 

They would be connected to a flasher relay ultimately, but the signal would branch out if more than one light is being flashed, So there will likely be a split in the harness coming off the flasher.

It is possible but I hope they did NOT incorporate the flasher relay function into the BCM. No clue on that.

I recently had a bulb socket on my 97 SC2 go bad. I think the epoxy part that the wires go into (as an encapsulated heat sink can eventually not dissipate enough heat and then the wires inside the epoxy melt and separate from the contacts INTERNALLY. This is a hypothesis. Ironically I bought a whole new taillight because I coud then broke my ankle so I have never installed it.

The Auras were heavy on electrical problems so it would not surprise me.

You can get piercing probes for your meter to backprobe the wires before they get to the socket. I would do this before going on a wild goose wiring chase

 

Thanks for the help Derf. If there was a flasher relay, wouldn't it be labeled in one of the fuse boxes? I can't find anything even remotely close to "turn signal" listed. I have heard that it was included in the BCM but I don't know where the BCM is or how to test that.

I've looked in the socket where the bulb goes and it looks perfectly fine. I tested it a little farther down the line at another connection and I wasn't getting voltage there either. I'm stumped. They didn't make this easy to fix. The left and right turn signal wires appear to go into the fuse box under the hood of the car but I don't know where it goes after that because I can't get the fuse box apart. Maybe it doesn't go into the fuse box but rather passes through.

 

The owner's manual will often tell you what is on what fuse.
the contacts under the fuse box may have burned up w out blowing the fuse.
If it is in the BCM, the BCM pinout should show you. Gotta be out there on the net.

 

The owners manual shows no fuse anywhere going to any sort of turn signal (Must be controlled by the BCM then?). I was also trying to take the fuse box apart a couple weekends ago but was unable to. There were screws on the top and a couple tabs around the side but I was unable to get it to move very far. Am I missing a step to take it completely apart?

I've also been poking around for a diagram of the BCM. Haven't found anything on the internet yet or in the owners manual.

 

A Haynes manual MIGHT help w fuse box disassembly.

When you were testing for V at the socket, did you test across the socket or the center Positive to CHASSIS ground. If the ground wire is bad, you will still see V when measuring w r t chassis ground.

Haynes manual may help w wiring schematics. Without them, you're flying blind. Especially if the turn signal flasher is controlled by the BCM.

 

I tested for voltage using the ground wire in the socket so I'll try grounding to the chassis tomorrow.Thanks for that tip.

I believe I found the BCM diagram for my car on another forum and it does show the turn signals on there. I will check for voltage at the BCM pin as well tomorrow. I'm guessing the BCM only outputs the positive voltage so I can ground to anywhere when testing like you said?

 

check vs chassis ground, the ground pin for the turn signal on the bcm, and also check that the ground pin on the bcm turn signal light is continuous w the chassis ground---I see no reason why bcm ground and chassis ground would be different.

You can do the continuity by measuring ohm (resistance) . Shouldn't be more than a few tenths of an ohm. Touch your leads together and subtract that resistance from your measurements to get a more accurate reading.