My 2008 TL's turn signals started acting funny recently. Two weeks ago, the right blinker started blinking rapidly. I thought maybe a bulb had gone out, but I didn't find a blown one. Then a week later, the left blinker would periodically not work. Two days ago, it just stopped working completely, but the right still blinks rapidly. Not sure how to troubleshoot this. I'm not seeing any turn signal specific fuses or relays in the manual. Looking for some level 1 things I can try.

 

So turn signal goes something like:
Turn signal switch -> Wiper/washer switch -> MICU -> Turn signal relay -> Bulbs

I believe that if anything up to MICU would fail, you would either don't have turn signal at all, or it would work just fine. Actual flashing (switching) is probably done only in relay, and MICU gives relay solid on/off signal. Relay is in under-dash fuse box. Probably cheapest and easiest thing to simply swap out for new without dealing with any multimeters, test lights, diagrams, etc.

 

Thank you for this quick reply. I don't see anything labeled MICU in the Interior Fuse Box diagram in the manual. Would it be labeled as something else?

 

MICU is build in into the under-dash (interior) fusebox, so basically they are the same thing.

 

Are we talking front signals, rear signals, or both?

Not to go all "did you try turning it off and then on again," but if it's the fronts, remember those are dual filament bulbs. The signal filament could go out, or vice versa, and there would still be another filament in the bulb on visual inspection.

 

Turn the hazards on and walk around the car to confirm everything is blinking correctly. The go back with the turn signals to confirm the same bulbs are flashing or not. This at least helps confirm if the bulbs are the culprit or something further upstream.

 

The symptoms are the same at the moment. All right side turn signals are blinking fast. All left side turn signal lights are off.

I also put on the hazards, and only the right blinked (fast). I tapped on the left front turn signal, and they all came on and went back to regular speed. Looks like I have a bulb or wire issue up there that I'm going to look at more.

 

So, today I changed out all four turn signal bulbs (2 front, 2 rear), and have the same symptoms. When turn signals are on, only the right flashes fast. The left does nothing. When flashers are on, only the right side are flashing (fast). The left turn signal worked normal for about 1 minute first thing this morning. Its all very strange. Not sure what else to try at this point.

 

Replace the turn signal relay

https://www.oemacuraparts.com/oem-pa...bC12Ni1nYXM%3D

Relay Assembly, Turn Signal And Hazard (Mitsuba) - Acura (38300-SHJ-A04)

 

Thanks. Looks like this is the same. I have a Mitsuba FR-3504 in the car now. I appreciate you being so helpful!

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