vent valve po52e71 - I have found thousands of the same issue with my car online. Mercedes covers this piece as an emission piece for Deisal Engine but not gas engines. This peice needs to be recalled and covered under emissions warranty asap.

- San Rafael , CA, USA

The Panoramic roof glass exploded suddenly. Throwing shattered glass pieces on the Highway and into the cabin of the car. No object or environmental conditions caused this incident. It just exploded while driving ~ 50mph

- Cincinnati, OH, USA

The Crank Ventilation code is showing up for a code and this has been happening to all of these GLC coupes. The check engine light comes on.

- Springfield, MA, USA

I got the P052E error at about 50k miles. Many GLC 300s apparently have this issue. I need a new crank case valve I believe and they put the part in a terrible place. Dealers charging over $1k in just labor.

- Horseshoe Bend , AR, USA

crankcase ventilation valve replacement required confirmed by the dealer. check engine light came on as notification. It appears to be a very standard problem on the the glc300 when they hit 60,000 miles and are out of warranty. $2000 repair

- Charlottesville, VA, USA

check engine light appears, car runs fine. the crankcase vent value was broken on our 2017 GLC300 car. a mechanic, with a computer, ran the codes and shared this happens many times to this car. the service advisor at mercedes shared the same input. happens all the time and should be covered under emissions warranty but isn't. this disfunction does not affect driving of car, just emission and (sales pitch to fix it) "could" affect engine in long term. i suspect this is a defective piece in the system that mercedes won't address or cover under emissions warranty.

- Shavertown, PA, USA

While driving on the I-75 North, the sunroof exploded as indicated in the picture attached. It is still unclear if the sunroof shattering was from a stray rock on the highway, or if the sunroof exploded on its own, however my concern is how the sunroof shattered and the quality of the material/glass used. What type of glass is used in this vehicle for it to shatter as it did? is this perhaps a sign of cheaper material being used on the sunroof. There are more pics than can show more of the damage.

- Fraser, MI, USA

Vehicle key-less entry locked out the driver and passenger with keys inside the vehicle while parked. Talked to other Mercedes Glc300 owners and they are experiencing same issue. This happened late at night with my wife and 7 year old daughter in a high crime area while I was out of town. Mercedes roadside assistance charged us $99.95 to unlock vehicle. This is a life threatening defect and should be acknowledged and addressed by Mercedes immediately.

- San Antonio, TX, USA

While driving on the I-5 into downtown san diego we heard a loud bam, a moment later heard cracking then shattered glass from my sunroof fell into the car. There was no one directly around us.

- Gilbert, AZ, USA