Recently purchased a 2004 MC40, and having an issue with the turn indicators not working properly.

Summary of situation:

• Passenger (RH) side rear and side marker turn indicators do not flash - not when lock/unlocking, using the indicator stalk, or with the hazard switch
• The passenger side front turn signals work correctly under all situations which I believe rules out the indicator stalk and hazard switch (please correct me if I'm wrong or let me know how I can troubleshoot those short of replacing them)
• Bulbs are both good - tried brand new bulbs but also swapped left to right
• Rear tailight ground is good, verified with test light and also because the rear passenger side running light and brake light functions correctly
• I've just replaced the battery as it went dead on me and tested as needing replacement. Issue happened before and after replacing battery
• Checked for a parasitic draw with a multimeter at the battery - appears to be normal
• All fuses in the engine and passenger compartment are good
• There is good continuity on the wire between the connector at the BCM and the rear tailight/turn signal - verified with a multimeter

Now given all of this, I believe it points to a BCM issue. However I've had an issue with the FRM in another BMW of mine, and with that and countless other experiences I've read FRM/BCM issues usually present themselves with multiple issues (several interior/exterior lights, power windows, power locks, etc.), but the only issue I have are these 2 turn signals.
I've gone ahead and taken out the BCM and all looks 100% normal. No corrosion or contamination and looks brand new. My car is a slicktop so water intrusion is less likely. Wiped the contacts clean anyway and reinstalled it, no bueno still.

My next step is to send the BCM to ECU PRO to get tested, but before I lose a couple weeks of use with the car and spend the money I was hoping for some other suggestions.

Some other notes, unsure if they're related. Car had a factory aux cord on it (at the time I thought it was the iPod connector) that I've just removed, issue persists. Also my rear fog light works on the driver's/LH side when I hit the rear fog switch on the panel, but the passenger's/RH side does not illuminate. Not sure if this is how it's supposed to be (I know many cars only have a fog light on one side) or if this is also an issue.

Any help is greatly appreciated!

 

Had a similar situation a ways back with the left rear turn signal / brake light not working in spite of bulb change. Turned out to be the socket assembly, which apparently go bad from time to time like all quality BMW electronics. Mine's a 2006, here is one listed for 2004, June production date:
https://www.realoem.com/bmw/enUS/sho...32#63216916395

That won't explain the front side marker light but on the off-off-chance that one has other cause(s), it could be worth a try before hauling out the BCM and downing the car for two weeks.

 

It's a good thought, but unfortunately not the problem. I just tried swapping the socket assembly left to right, and the problem persists on the right side but the lights still work on the left side.

 

2017 Mini Clubman S

If you guys could help me, my driver side turn signal stop working. I replaced bulb, checked connections and bulb still won't work. I get a hyper blinking light. The other side works fine. Front and rear driver signal works but blinks fast. Any ideas?