The driver's seat belt is locked and the retractor is not working without any reason. The front adaptive cruise control radar is also not working, along with the crucial blind spot sensor. Because of this, the vehicle cruise control (even without adaptive mode) is not working at all. This is a big safety issue and it is illegal to even drive this car without the seat belt working.
2012 Mercedes-Benz ML-Class seatbelts problems
moderate 3 complaints filed with NHTSA · avg repair $500 · see seatbelts across all vehicles →
Complaints
3
Recalls
0
Avg fix
$500
When does it fail?
Of the 3 seatbelts complaints filed for the 2012 Mercedes-Benz ML-Class, here's the actual mileage breakdown — failures cluster heaviest at 50,000-75,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What owners are reporting 2 most recent
Seat belts will not extend. When trying to buckle seat belt, the belt retractor locks as you try to extend, preventing you from buckling your seat-belt. Affects both driver and passenger seat-belts. Intermittently happens and seems to be temperature related. More likely to happen when it is warm.
Had seatbelts trouble with your 2012 Mercedes-Benz ML-Class?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the seatbelts problem on the 2012 Mercedes-Benz ML-Class?
It's a documented issue but not catastrophic. 3 complaints have been filed. Repairs average $500 and most owners catch it before it causes a breakdown.
At what mileage does the seatbelts typically fail?
Based on the 3 complaints filed, seatbelts issues most often appear around 43,630 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $500 for seatbelts repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to seatbelts?
No active recalls currently cover seatbelts issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2012/Mercedes-Benz/ML-Class.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.