Mercedes-Benz bulletin LI54.70-P-080191

Complaint Consistently reproducible erroneous parktronic warnings from front with every key cycle. Cause The parking sensors are detecting the front brush guard. Remedy Complaint must be consistently reproducible and can occur multiple times a key cycle without obvious cause. NOTE: The parking system serves solely as an aid. Please review both the system function and system limitations as shown in the Operator's Manual. Certain environmental factors can affect system functionality such as hot exhaust gases or extreme heat, sensor interference, or other outside influences or aftermarket modifications. If after verifying the complaint is consistently reproducible: 1. Determine if the complaint is reproducible only in high ambient temperatures. If complaint does not occur in cooler ambient temperatures, it is due to system limitations. You may proceed with the below work but the vehicle may be released afterwards as it is due to system limitations. 2. Remove the brush guard and verify the park distance sensors function as expected. 3. Reinstall brush guard and adjust so that it is as far away from the park sensors as possible. This typically means moving the bar further away at the bottom and closer at the top. 4. Check function. If the concern is still consistently reproducible, please apply clear matte film to the locations as shown below at a minimum, although the clear matte film may be applied to the whole brush guard. Picture: Above shown is the 465 brush guard variant. Although similar to the 463, there are some key differences such as the 465 being fitted with a front camera.

Owners of the 11 model years this bulletin names have filed 40 complaints with NHTSA since 2015. 11 of them name Electrical System, Forward Collision Avoidance, Back Over Prevention — the same broad component group this bulletin is filed under. NHTSA groups complaints coarsely, so that means the same area of the vehicle, not necessarily the same fault.