At about 40,000 miles the parking brake began sticking and was difficult to release. This was replaced under warranty. It began happening again . I spoke to the Mercedes usa and they said I would have o pay to replace it. I believe this part is defective.
2012 Mercedes-Benz C-Class brakes problems
severe 13 complaints filed with NHTSA · avg repair $450 · see brakes across all vehicles →
Failure mileage
Complaints
13
Recalls
0
Avg fix
$450
1crash
When does it fail?
Of the 13 brakes complaints filed for the 2012 Mercedes-Benz C-Class, here's the actual mileage breakdown — failures cluster heaviest at 75,000-100,000 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 stands out
Of the 14 model years of Mercedes-Benz C-Class we track for brakes problems, this one carries the most owner complaints on file — 13.
No new NHTSA brakes complaint has been filed on this vehicle in over 5 years — the issue may be aging out of the active population.
The failure pattern owners describe
Buyer takeaway: The 2012 C-Class brake system shows a pattern of vacuum pump failures that eliminate power assist with no warning, resulting in hard-pedal or no-brake incidents at highway speeds. Rear brake lines corrode and leak at higher mileage, and some owners report master cylinder failures—none covered by recall despite multiple reports.
Owners of 2012 Mercedes-Benz C-Class models report brake failures across multiple failure modes. The most frequent complaint involves the brake vacuum pump: at mileages ranging from 25,000 to 96,000 miles, the pump stops working, eliminating power assist. When this happens, the brake pedal becomes extremely hard and unresponsive to normal pressure, or fails to work entirely even with maximum pedal force. These failures occur without warning—no lights illuminate, no dashboard messages appear—often on highways at speeds of 60–75 mph. Owners describe pulling hard on the pedal with zero response, forcing them to use the parking brake, downshift, or collide with obstacles to stop.
Several owners report that vacuum pump replacement at Mercedes dealerships did not permanently resolve the problem. One owner had the pump replaced twice by authorized dealers and still experienced recurring brake failure.
At higher mileages (110,000–120,000 miles), rear brake lines corrode severely and leak. These lines are often discovered during unrelated service visits, with no prior warning symptoms.
One owner reports brake-box (master cylinder) failure on the highway, with a hard pedal and total loss of braking power, again with no sensor faults or visual indicators.
A parking brake mechanism becomes sticky and difficult to release at 40,000 miles; after warranty replacement, the problem recurs. Mercedes USA denied coverage for the repeat failure, citing it as a customer-pay repair.
Same Mercedes-Benz C-Class brakes reports on nearby years: 2009
Failure modes owners describe
Brake Vacuum Pump Failure
The brake vacuum pump loses function, eliminating power-assist to the braking system. When this occurs, the brake pedal becomes extremely hard and unresponsive at normal pedal pressure. Drivers must apply extreme force to the pedal to achieve any braking effect, or braking may not occur at all despite maximum pedal effort.
When: Mileage ranges from 25,000 to 96,826 miles; failures reported during highway and city driving at various speeds
Symptoms owners cite: Brake pedal becomes extremely stiff or hard; Brake pedal goes to floor with no braking response; Vehicle fails to slow or stop despite brake application; No warning lights or dashboard indicators; Occurs randomly without prior warning
Codes mentioned: Brake vacuum pump defect
Repairs/costs cited: Vacuum pump replacement performed at Mercedes dealerships; failures recurred in at least one case after replacement
Recalls/TSBs owners mention: No recalls or TSBs mentioned; manufacturers stated unable to find issues in some cases or provided no assistance
Rear Brake Line Corrosion and Leakage
Rear brake lines become severely corroded and develop leaks. This typically occurs at higher mileage and is often discovered during unrelated service or inspections. The corrosion compromises the structural integrity of the lines and their ability to contain brake fluid pressure.
When: Approximately 110,000 to 120,000 miles
Symptoms owners cite: Rear brake line leaking; Severe rust visible on rear brake lines; Often no warning lights or symptoms until discovered during inspection
Repairs/costs cited: Brake line replacement needed; in some cases not covered under extended warranty and owners declined repair
Recalls/TSBs owners mention: No recall coverage; manufacturer stated VIN not included in recalls; manufacturer made aware but provided no assistance
Brake Box (Master Cylinder) Failure
The brake box (master cylinder) located behind the motor becomes defective or breaks, resulting in complete loss of brake function. The component shows no visual fault codes or sensor indicators, making it difficult to diagnose without physical inspection.
When: At least one failure on highway at 75 mph speed limit
Symptoms owners cite: Hard brake pedal; Complete loss of power brakes; Brake pedal pressure does not slow vehicle; No alarms or visual indicators
Repairs/costs cited: Brake box replacement required; component typically not on visual maintenance checklist
Parking Brake Stickiness and Release Failure
The parking brake becomes difficult to release and sticks in the engaged position. The problem recurs after warranty repair, suggesting a design or material defect in the parking brake mechanism.
When: Initial failure at approximately 40,000 miles
Symptoms owners cite: Parking brake sticks and is difficult to release; Recurring problem after repair
Repairs/costs cited: Parking brake replaced under warranty; problem recurred; subsequent repairs required out-of-pocket payment
Recalls/TSBs owners mention: Mercedes USA stated customer would pay for subsequent replacement; no recall or warranty coverage offered for recurring issue
Brake Caliper Paint Peeling
Clear coat paint peels off the brake calipers, a cosmetic defect. Dealership did not replace or repair the defective component.
When: Unspecified
Symptoms owners cite: Clear coat paint peeling from brake calipers
Recalls/TSBs owners mention: Dealer declined to replace or repair
Synthesized from 13 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
Had brakes trouble with your 2012 Mercedes-Benz C-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 brakes problem on the 2012 Mercedes-Benz C-Class?
It's a meaningful issue. 13 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $450.
At what mileage does the brakes typically fail?
Across the 10 complaints that reported odometer mileage, most brakes failures cluster between 80,000 and 120,000 miles, with the median around 103,000. A quarter of owners report trouble before 80,000; a quarter make it past 120,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $450 for brakes 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 brakes?
No active recalls currently cover brakes 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/C-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.