Mercedes-Benz USA, LLC recall 21V197

Related investigation

NHTSA opened an investigation that led to this recall.

• PE21001PEEscalated to RecallOpened Jan 8, 2021
  Front Roof Panel Detachment

Affected vehicles (27)

Component / system

Defect

Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2020 C300 Coupe, C43 Coupe AMG, C43 AMG, 2015-2020 C300, GLA250, 2016-2018 C350e, CLA45 Coupe AMG, 2015 C400, S65 AMG, 2015-2019 C63 AMG, 2016 C450, 2015-2016 GLA45 AMG, S600, 2016-2020 GLC300, 2017-2019 GLC43 AMG, GLE43 Coupe AMG, 2014-2019 CLA250 Coupe, 2014-2015 CLA45 AMG, 2018 GLC63 AMG, 2014-2017 S550, 2018-2020 S450, 2016-2019 GLE63 Coupe AMG, 2016 GLE450 Coupe, 2014-2020 S63 AMG, 2018-2019 S560, and 2019 GLC350e vehicles equipped with a panoramic sunroof. The front roof panel located between the windshield and the panoramic sunroof may not have been bonded correctly to the vehicle during a prior repair.

Risk / consequence

The adhesive bonding of the front panel might deteriorate, possibly causing the front panel to detach from the vehicle and become a road hazard, increasing the risk of a crash.

Remedy

Mercedes-Benz dealer will remove the bonded panel and will install a new front panel by following the detailed repair instructions and using the approved primer, cleaner and adhesive, free of charge. Owner notification letters were mailed on September 3, 2021 and October 26, 2021. Owners may contact MBUSA customer service at 1-800-367-6372.

Chronology of events

1. June 2020

   In June 2020, NHTSA raised two VOQs to Mercedes-Benz describing instances in which the front roof panel forward of the panoramic sunroof had allegedly detached from the vehicle while it was traveling at highway speeds. MBAG launched an investigation and was able to verify from its internal documentation that in both cases the incorrect adhesive was used to bond the panels during a previous repair. MBAG also began to analyze its internal data related to detachment of the front roof panel to understand whether the incidents were indicative of a broader trend or isolated events and found a number of sporadic reports submitted between 2018 – 2020 involving claims of cracked or partially detached panels. MBAG also observed that all involved vehicles that had also undergone a prior service repair to the front roof panel. MBAG began to analyze whether there was a more systemic issue and whether it was related to a prior repair of the front roof panel. MBAG provided an update to NHTSA in December 2020 and NHTSA opened its Preliminary Investigation in January 2021. MBAG’s technical analysis was carried out from late 2020 and into the first quarter of 2021 and included an analysis of possible deviations from the published repair instructions as not all vehicles that had undergone a prior service repair necessarily reported a subsequent issue with the bonding of the panel. Test setups were prepared by recreating various repair scenarios where an incorrect pre-treatment and bonding adhesives other than the specific adhesive that had been approved for this repair. Sample roof panels were also returned from the field and analyzed which indicated how the pre-treatment, cleaning and primer application were actually being applied by Mercedes-Benz workshops and any third-party sublets and confirmed that there were deviations from the repair procedures. Please see updated Chronology Supplement.

Notification schedule

Dealer notification

MAR 26, 2021 - MAY 14, 2021

Owner notification

NR - NR