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3 months 1 day Marlon.

Marlon I have this exact same problem. I tried replacing the bulb and bulb socket, no luck. I took it to my indy and they came back and said that the passenger rear tail light assembly has failed and needs to be replaced. Like you, I've put some LEDs in my car - interior and trunk mostly, although the reverse lights are LEDs too (OEM lights were so dim they didn't illuminate anything, even from a foot away). Everything else is stock. My indy said the LEDs in the reverse lights should not cause a problem, but that's my next step - I will try putting the OEM incandescents back in and see if the error goes away. Wish me luck...

IVI wrote:Marlon I have this exact same problem. I tried replacing the bulb and bulb socket, no luck. I took it to my indy and they came back and said that the passenger rear tail light assembly has failed and needs to be replaced. Like you, I've put some LEDs in my car - interior and trunk mostly, although the reverse lights are LEDs too (OEM lights were so dim they didn't illuminate anything, even from a foot away). Everything else is stock. My indy said the LEDs in the reverse lights should not cause a problem, but that's my next step - I will try putting the OEM incandescents back in and see if the error goes away. Wish me luck...

Yeah - ditch all the LEDs revert to OEM bulbs and if the error doesn't clear straight away give at least 2 or 3 long drives. Mine kept erroring randomly for several weeks after I'd swapped out the LEDs. The error would clear on restarting the engine. I lived with it like that as I say for several weeks and then it error'd less and less until it disappeared completely (well so far anyway). Puzzled the hell out of me

Scooba_Steve warned me against Canbus LEDs and I'm just waiting for him to tell me for the umpteenth time "I told you so"

I've got a day-long road trip with the Z club tomorrow, so that'll be one down...

If you can read error codes it should its which bulb(s) are causing the error.
Interior LEDs won't cause you a problem, I have reverse LEDs and these are not monitored by the system (presumably because they're not required by law?).
I don't have to tell Marlon any more, it's etched into his being!

Well... after replacing the LED bulbs with the OEM incandescents, the problem appears to be resolved. Here's what happened:

1. Replaced LED bulbs with OEM incandescents.
2. Went on road trip with car club. Stopped several times along the way.
3. For the first several stops, after starting the car, no error popped up. However, on first use of the turn signal after starting the car each time, I would get two normal blinks and then error + hyper blinking after that.
4. After 3 stops like this I discovered that I could use the signal for the first two normal blinks and then shut the turn signal off before the hyperblink or dash warning error occurred. Drove like this for 50 miles, only using the turn signal for two blinks to indicate lane changes.
5. After final stop before heading home, I decided to test extended use of turn signal. Two normal blinks, then... more normal blinks! No errors!

I have no idea where the weak link is, but apparently when BMW says don't mess with Texas they mean business. I'm happy I didn't just take the shop guy at his word and go out and buy $300 worth of tail light assembly though. And I still want to find a competent electrician who can replace all (ALL!) the incandescents in the car with LEDs for me, minus the dash warnings.

IVI wrote:Well... after replacing the LED bulbs with the OEM incandescents, the problem appears to be resolved. Here's what happened:

1. Replaced LED bulbs with OEM incandescents.
2. Went on road trip with car club. Stopped several times along the way.
3. For the first several stops, after starting the car, no error popped up. However, on first use of the turn signal after starting the car each time, I would get two normal blinks and then error + hyper blinking after that.
4. After 3 stops like this I discovered that I could use the signal for the first two normal blinks and then shut the turn signal off before the hyperblink or dash warning error occurred. Drove like this for 50 miles, only using the turn signal for two blinks to indicate lane changes.
5. After final stop before heading home, I decided to test extended use of turn signal. Two normal blinks, then... more normal blinks! No errors!

I have no idea where the weak link is, but apparently when BMW says don't mess with Texas they mean business. I'm happy I didn't just take the shop guy at his word and go out and buy $300 worth of tail light assembly though. And I still want to find a competent electrician who can replace all (ALL!) the incandescents in the car with LEDs for me, minus the dash warnings.

I hope its all over but don't be surprised if the problems hang a round intermittently for a while. It's like these LED's haunt the car for a while after being exorcised

Marlon wrote:I hope its all over but don't be surprised if the problems hang a round intermittently for a while. It's like these LED's haunt the car for a while after being exorcised

Good to know, thanks for posting about your experience with this for the rest of us!

IVI wrote:Well... after replacing the LED bulbs with the OEM incandescents, the problem appears to be resolved. Here's what happened:

1. Replaced LED bulbs with OEM incandescents.
2. Went on road trip with car club. Stopped several times along the way.
3. For the first several stops, after starting the car, no error popped up. However, on first use of the turn signal after starting the car each time, I would get two normal blinks and then error + hyper blinking after that.
4. After 3 stops like this I discovered that I could use the signal for the first two normal blinks and then shut the turn signal off before the hyperblink or dash warning error occurred. Drove like this for 50 miles, only using the turn signal for two blinks to indicate lane changes.
5. After final stop before heading home, I decided to test extended use of turn signal. Two normal blinks, then... more normal blinks! No errors!

I have no idea where the weak link is, but apparently when BMW says don't mess with Texas they mean business. I'm happy I didn't just take the shop guy at his word and go out and buy $300 worth of tail light assembly though. And I still want to find a competent electrician who can replace all (ALL!) the incandescents in the car with LEDs for me, minus the dash warnings.

You can code out the bulb check yourself - get a cable and use NCS Expert, plenty of guides online. If you buy good quality, non-CANBUS compatible LEDs from Osram/Philips etc. then you won't have issues.

Marlon wrote: ↑Mon Feb 22, 2016 10:29 amI can't get to them - its one of those ridiculous bulb sockets that are virtually inaccessible, I'm having to work blind using a long screwdriver just to get the bulb in and out.

Hey Marlon, did you manage to sort this one out? I've got the same problem but the failed indicator bulb is intermittent. I've replaced the bulb and bent out the contacts on the bulb holder but to no avail. Next step will be to pull the bumper and headlight off and check all of the contacts...

Mangozac wrote: ↑Sun Jan 14, 2018 12:18 am

Marlon wrote: ↑Mon Feb 22, 2016 10:29 amI can't get to them - its one of those ridiculous bulb sockets that are virtually inaccessible, I'm having to work blind using a long screwdriver just to get the bulb in and out.

Hey Marlon, did you manage to sort this one out? I've got the same problem but the failed indicator bulb is intermittent. I've replaced the bulb and bent out the contacts on the bulb holder but to no avail. Next step will be to pull the bumper and headlight off and check all of the contacts...

I did manage to replace the bulb 'blind' using a long screw driver - pitta if you have to remove the bumper!

You could just code out car to stop checking when cold and warm so no warning light , navcoder software does it "front blinkers" & "rear blinkers"
sorry for the poor pic.

Marlon wrote: ↑Sun Jan 14, 2018 10:57 am I did manage to replace the bulb 'blind' using a long screw driver - pitta if you have to remove the bumper!

I feel like that would be way easier just removing the bumper!

mac27040 wrote: ↑Sun Jan 14, 2018 1:28 pmYou could just code out car to stop checking when cold and warm so no warning light , navcoder software does it "front blinkers" & "rear blinkers"
sorry for the poor pic.

Fair suggestion, but I'd rather not disable the fault checking. It goes have a legitimate function

So how did you guys get it fixed?