snowflakeGL

Hi I have a 2013 GL550 bought since new and it's always been serviced through the MB dealership. Recently I've been having "Blind Spot Assist not not operable" messages randomly, sometimes upon startup or sometimes during driving. Taking it to the dealer they couldn't figure out the issue and told me that "external interference is normal". I didn't accept that answer and told the service advisor if its normal than why have it only started to occur after 10 years of ownership? Before I take it to another dealership, does anyone else have this similar symptom and how have they resolved it? Thanks in advance.

oldmangrimes

Are your turn signals working when this happens? I had to replace the part of the steering column that has the turn signal stalk. It's a common problem with this generation of Mercedes, it happens to other Mercedes models too. When you activate your turn signal, the vehicle checks the blind spots, but that exchange of information doesn't happen properly once the steering column module starts to fail.
https://mbworld.org/forums/gl-class-...acting-up.html

snowflakeGL

To be honest I haven't noticed the turn signals not working when the blind spot assist is not functioning.

Jason Stewart

I had a similar problem, and in my case it had to do with a faulty trailer towing module. According to what the dealer technician told me, when there is a trailer attached to the car, it will automatically disable the lane keep assist system and the Blindspot assist system; in my case, there was no trailer attached, and the faulty module was sending confusing messages to the rest of the car which caused this message to appear (and, weirdly, eventually disable the turn signal blinkers).

snowflakeGL

This actually might be my cause, I routinely have bike racks and cargo basket installed and might be why the blind spot assist is going crazy. I'll mention to my service advisor and see what he thinks. Appreciate the post.

nycrx7

oops, should have posted here... mods, if you would like to delete my thread yesterday...

I have a 2015 GL450, and jsut started to have BSA issues... or rather, it turned off, and does NOT let me turn it back on. No error message. In more detail:

- I do not get an error message, most people seem to get the "Blind Spot assist inoperable" type of message. I do not get one on start up. I'm not sure if a basic error code reader would even catch something like this, but nothing comes up there either when I checked.
- the triangles on the sides do not light up at all... no yellow, red, nor blink. My turn signals work, no problem.
- When I go through the safety assist menu ... it informs me that Blind Spot Assist "Sensors are deactivated" ... but when i click "OK", nothing happens. It just does not turn go to "activated".
Has anyone had this problem? Scared of what the dealer is going to charge me to fix this... ugh...
Thank you,

Stevo2323

I wondered if these two issues were related. My issue started out with getting BSA inoperable messages sporadically…would go out, then come back on, etc. Then my turn signal would randomly stop working, but if I turned the car off, then back on, they’d work again. When I was able to get into the menu before the BSA would act up, I just turned it off, and now my turn signal issue went away. Also, my hazard lights worked during the whole issue, so definitely a weird situation.

rapidoxidation

Identical issue on my '13 ML. It was predictable when roads were wet, so I felt it didn't have anything to do with the turn signal stalk that was snug and dry inside the car. Took each blind spot sensor off the car's rear corners, cleaned the sockets (male and female), and liberally applied silicone grease (plain old plumber's grease) to both sides and squished them together in a (seemingly successful) attempt to drive out and keep out moisture. So far, the "fix" has mostly worked. Enough, at least, to where if things go awry again I'm confident that dumping a pocket full of cash on two new blind spot sensors will fix the problem. Until things fail, I might just keep liberally reapplying the silicone every now and then. Corrosion kills these sensors.

L&N Caravan

BSA toggled with trailer connect at rear trailer module. Also, check rear SAM module for “low voltage” or “out of range” voltage. Both are resettable via diagnostic tool interface. Also, check trailer wiring harness under rear bumper- rodent damage, stray wires, insulation stripped/exposed etc. If physical inspection checks out, most likely the modules. The situation where everything goes back to normal upon restart just indicates the reboot software process is working at the hardware+software interface, then “something” happens. If the physical hardware “something” can be ruled out, most likely a malfunctioning module.

mcoady1

Mine was the actual mirror triangle that went out and the dealer couldn't figure it out. I could watch it flicker when activated (another car in my blind spot) then would deactivate and throw the inoperable code. There was a separate code for the mirror in the door module. An ebay replacement mirror did the trick.

BlownV8

Same here, got a cheap mirror and swapped out that piece and kept my factory one.

Mikegl550

Mine came on when I was towing a trailer so if it pops on one of the sensors in the rear is bad or shorting out or something is blocking it. Could be dust I also had an issue when I'd get a ice storm it would pop on too

coffla

I have similar issue with a 2012 GL550