Left and right signal light don't work from inside or outside. Single swipe wiper doesn't, but timing wiper works. All the buttons on the steering wheel work. The hazard lights work both in and out.

Ok since your hazard lights work you've ruled out the lamps, the BCM, and the wiring to the BCM. That leaves the spiral cable and the switch. You have already replaced the switch so it's likely good, that leaves the spiral cable. The spiral cable handles ALL functions from the steering wheel including the turn signal and wipers, you have multiple systems going through the spiral cable that are not functioning, blinkers and part of the wiper.

The problem is LIKELY the spiral cable. Read a couple guides on replacing it so you don't screw up the steering angle sensor.

Im dealing with the same Issue. However. My BCM was wet and the car went haywire. It was telling me no key. The headlights would turn on by themselves. Even when the switch was in the off position. The car would have a nonstop beep noise. It wouldn’t start. But I disconnected it and let it dry in the sun for a few hours. Connected it back and everything worked fine. Except for the same issues you’re having. So idk if I need a new BCM all together. But other than my signals individually and my single wipe function on the wipers everything else works just fine. Idk if that helps. But it’s a start to look by the passneger side floor under the carpet for any water

My car is having the exactly same problem after the bcm module got wet. Were you able to get your fixed ? and what was the fix ?

I've returned to this thread i previously made. The issue with my blinkers seemed to go away after a couple days when i replaced the fuses. But now a year later i am having an issue i'd like some input on if anyone knows.

My key unlocks/locks the car perfectly fine but the car won't start with the push to start! I can set it on lock/acc/on mode and the fans spin but the engine wont crank.. Earlier today the car started fine when i moved it to a different parking spot but i noticed the rpm's where high for no reason and thought nothing of it. Now when i try to start it everything comes on on the dash, the radio/the air conditioning seems to work fine, but the dash also has a key icon.
I am thinking this is an issue with the Steering Column Lock Actuator what do you think? Was that high rpm related?

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I've been working through the issue you've helped diagnose before on my 2008 G35x. In a nutshell, the turn signals stopped working (no internal or external lights) but the hazards work fine (internal and external). I've replaced the headlight/turn signal/wiper column switch AND the clock spring (retained the original angle sensor, which could be a mistake?) and now I'm thinking that what's left is the BCM. In other words, the signal is making it from the switch and clockspring but the BCM is failing to pass along to the turn signals. Plausible? Other thoughts? I can't find a turn signal fuse anywhere on this car... Thanks!

Have you figured it out yet?

I pulled the BCM out and hit it hard with electrical contact cleaner and did the same with the grounds near the BCM. My turn signals came back to life. So, not the signal switch and not the spiral switch, the BCM circuitboard and grounds. Water from the plugged sunroof drain had probably caused corrosion I could not see. If you ever have wet carpet on the passenger side I would start here! And then fix the drain (Youtube videos).

Hmm im going to try that i did have the leak months ago i rerouted it the ac/drain so maybe? because once i installed my new turn signal switch it worked for a few minutes then the next day i was swapping clock spring out i tried using it stopped but wipers are good

I have same the same issue my horn works as well as my cruise control the light on the dash turns on for it Audio I can’t check bc my aftermarket steerio is out (I think) what could I do to fix this issue ?