Which parts fail
Components named in complaints (buckles, retractors, anchors and pretensioners).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2008 Mercedes-Benz C300 owners, lightly cleaned up (personal details are redacted by NHTSA).
After repair done on the confirmed recall airbag computer/module my vehicle became immobile, malfuctioned. The vehicle warning lamps alerted the airbag malfunctioned, srs malfunction. I seeked service for repair of this recall by experts. This safety issue is still ongoing and urgency is needed for this to be resolved.
Car has been in and out of the shop. Initially I have been contacting Mercedes about airbag messages and continued message of SRS Malfunction on dashboard. Airbags had been recalled and supposedly replaced on multiple occasions. This SRS continues to remain even after repair or being seen for this issue only for other components to have failed and me having to pay for those in the process. The SRS Malfunction remains an issue until the next issue is affected. Recently an entire Electronic SAM Module Component was replaced as the culprit only to have more issues and the SRS remained. Mercedes has contended that each time they saw the vehicle the the SRS Malfunction was not the problems while other documents were repaired such as battery and SAM. In the meantime since then the car has stalled, components that were working are no longer inoperable. …
Jan 2015 started care and immediately SRS and seatbelt light message appeared on dash. Late fall 2015 received recall letter, called mb of catonsville, received/went to appointment for repair. Missed time from from work only to be told w/n the hour part was not available, I would receive a call when it came in. Late May 16 I received another recall letter from mbusa referring me back to the dealer. Wednesday 06/15/16 I contacted mbusa who explained to me that the part for the airbag was not in but the sra part was available at the dealer. I was directly connected to mb of catonsville by mbusa and was assured part was there/ I was given an appointment next day Thursday at 8:15 a.m. At appt., 2 hours later I received a call from the svc mgr. Part was not available. It might take until Monday June 20, 2016. It is now Tuesday June 21, 2016. …
Transfer case reseal. I have a 2008 C300 I bought with 56K miles on it, I had to have the wheel bearings replaced immediately. When this service took place, I was informed that I need to have my transfer case resealed and the cam shaft magnets replaced. This car has such low miles on it. I do not understand how this is needed at this time. I have seen on many boards, this is a common problem. Why hasn't mb recalled this yet? It appears the 2008 model is plagued with problems as I have had to replace the steering lock as well as it failed. Again, common problem and not recall. I now have a seatbelt sensor that faulty. All of this before I have even hit 100K. My 2001 ml is well over 200K and I have never had these issues with the ml.
Rear passenger seat belt restraint buckle will no longer make contact with metal seat belt latch. Does not insert completely and does not click. Mechanism appears to suddenly not allow for connection to lock and secure safety belt for a passenger to be secured. Not safe and secure for use at this time. Resistance has appeared with other rear seat belts as well. There is no blockage or disruption other than the mechanism within the seat belt buckle itself that does not click or stay in place when attached with the metal seat belt latch. Vehicle was in motion when seat latch became unattached as my child was secured in a safety seat and it was notices that the latch became unfastened involuntarily
Tl* the contact owns a 2008 Mercedes-Benz C300. While driving at low speeds, the passenger side air bag warning light illuminated. In addition, the front driver side seat belt retracted while there was a passenger in the seat. The failures recurred on numerous occasions. The vehicle was not diagnosed nor repaired. The VIN was included in NHTSA campaign number: 15V711000 (air bags); however, the part needed to repair the vehicle was unavailable. The contact stated that the manufacturer exceeded a reasonable amount of time for the recall repair. The manufacturer was not notified of the issue. The failure mileage was 70,000. VIN tool confirms parts not available.
Tl* Takata recall. The contact owns a 2008 Mercedes-Benz C300. While driving at any speed, the SRS light turned off and on. After two months, the light remained illuminated. The contact called the manufacturer and was referred to a local dealer where it was diagnosed that the driver side seat belt buckle was faulty and needed to be replaced. The dealer warned the contact that the replacement of the seat belt buckle May not stop the SRS light from illuminating. The failure was remedied. The contact received notification of NHTSA campaign number: 15V711000 (air bags); however, the part to do the recall was unavailable. The failure mileage was 156,000.
Tl* the contact owns a 2008 Mercedes-Benz C300. While driving approximately 40 MPH, the air bag SRS warning indicator illuminated intermittently. The failure occurred while driving various speeds. The vehicle was taken to the dealer where it was diagnosed that there was a failure with the driver side seat belt sensor. The contact mentioned that the seat belt sensor should be included in the recall associated with NHTSA campaign number: 15V711000 (air bags). The manufacturer was notified of the failure. The approximate failure mileage was 85,000.
SRS malfunction drivers side warning came on. Only comes on when my husband drives, never has with me and I am the primary driver daily. Dealership wants to replace the seat belt buckle which is $500 - $1000. Why does it only do this when my husband drives? They cannot tell me that. And we can go from 1 MPH up to anything. Help!
For unknown reason, a warning about SRS restraint system driver side failure. Unsure if this is air bag, or seat belt related. Dealer wanted $2200. To fix. Outrageous safety issue. From online search this seems to happen regularly to mb products. Why has dot not taken action. Thank you for a response.
Seat Belt complaints in other C300 years
Frequently asked questions
How common are seat belt problems on the 2008 Mercedes-Benz C300?
NHTSA has 22 complaints about the seat belts of the 2008 Mercedes-Benz C300, 3% of the model year's 672 complaints. The component named most often is front › buckle assembly (1 mentions).
Is there a recall for 2008 Mercedes-Benz C300 seat belt problems?
No. NHTSA lists no seat belts recall for the 2008 Mercedes-Benz C300, though it has 7 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2008 Mercedes-Benz C300 seat belt problems start?
Half of the complaints with a recorded mileage happened before about 75,000 miles.
Is it dangerous?
Owners linked 0 crashes, 0 fires and 1 injury to seat belts problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.