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My wife and I have had a 2018 E400 (wagon, not a sedan, sorry) for just shy of a year now. Recently we had a bunch of errors pop up onto the screen like "active blind spot assist inoperative", "adaptive cruise control inoperative", "active brake assist functions limited" and a 4th one I can't remember.
We took it to a mechanic who told me the distronic sensor would need to be recalibrated, which happened and the errors went away. After this, we still seemed to have some smaller issues, like the blind spot sensors not working for about a week, which seemed to slowly be coming back, although we don't really see the orange light pop up anymore, mostly just the red one. But it seems that sometimes the parking sensors just don't detect anything.
On the way to work ~2 weeks later, all errors popped back up again, but when driving back home in the afternoon, they were gone again.
We took it to the same mechanic again, who looked for error codes and this time found that the accelerator pedal assembly was showing errors, so that one ended up being replaced (covered by extended warranty, so that ended up being okay). Thinking that maybe this was causing some electric gremlins.
However this morning, when parking the car, it didn't detect the curb, whereas it would before all of this happened. (And we still barely see the orange blind spot warning pop up)
So yeah, I was just wondering if anyone has had something similar, or if anyone had some tricks or tips on what to do next?
Also sorry, it's my first time posting, so I hope I gave enough info and details.
One of the first things to check when having intermittent sensor/electrical issues is system voltage. If you still have the factory battery and voltage capacitor/aux battery, you're fortunate but you're on borrowed time. It's always good to first eliminate these as the source.
One of the first things to check when having intermittent sensor/electrical issues is system voltage.
If you still have the factory battery and voltage capacitor/aux battery, you're fortunate but you're on borrowed time.
It's always good to first eliminate these as the source.
that is an excellent first step to mute Gremlins.
Last edited by CaliBenzDriver; Feb 25, 2026 at 07:29 PM.
My wife and I have had a 2018 E400 (wagon, not a sedan, sorry) for just shy of a year now. Recently we had a bunch of errors pop up onto the screen like "active blind spot assist inoperative", "adaptive cruise control inoperative", "active brake assist functions limited" and a 4th one I can't remember.
We took it to a mechanic who told me the distronic sensor would need to be recalibrated, which happened and the errors went away. After this, we still seemed to have some smaller issues, like the blind spot sensors not working for about a week, which seemed to slowly be coming back, although we don't really see the orange light pop up anymore, mostly just the red one. But it seems that sometimes the parking sensors just don't detect anything.
On the way to work ~2 weeks later, all errors popped back up again, but when driving back home in the afternoon, they were gone again.
We took it to the same mechanic again, who looked for error codes and this time found that the accelerator pedal assembly was showing errors, so that one ended up being replaced (covered by extended warranty, so that ended up being okay). Thinking that maybe this was causing some electric gremlins.
However this morning, when parking the car, it didn't detect the curb, whereas it would before all of this happened. (And we still barely see the orange blind spot warning pop up)
So yeah, I was just wondering if anyone has had something similar, or if anyone had some tricks or tips on what to do next?
Also sorry, it's my first time posting, so I hope I gave enough info and details.
You are becoming acquainted with the various ways your E400 request service.
These networking faults are built-in signs of unstable module voltage disruptions.
Once you have a good battery set, you will want to keep them from getting drained to reach low voltage - Use a float charger (CTEK/NOCO/...) to begin with as primary protection.
Try to never jump your car flat battery, prefer using a battery charger instead. It limits the charge current under 10Amps instead of unlimited toasting power.
Last edited by CaliBenzDriver; Feb 25, 2026 at 07:30 PM.
