According to Au7o's analysis of 890+ owner reports, the 2012 Mercedes-Benz SLK/SLC has 2 documented known issues. No issues are rated critical, indicating generally reliable ownership. The most commonly reported issue is Vario Roof Retractable Hardtop Hydraulic Leak with 890 owner reports. Across all issues with published estimates, repair costs range from $120 to $2,500. DIY maintenance guides at au7o.io.
On the 2005-2020 Mercedes-Benz SLK/SLC, the Vario Roof retractable hardtop on both R171 and R172 SLK/SLC models develops hydraulic leaks at the cylinders, lines, and pump. The most common leak points are the roof lock cylinders and the main lift cylinders. Leaking hydraulic fluid drips into the trunk area and can damage interior trim and the spare tire well.
Identify and replace the leaking hydraulic cylinder or hose. Top off with the correct hydraulic fluid (CHF 11S). The hydraulic pump is located in the trunk — inspect it for leaks as well. Aftermarket hydraulic cylinder rebuild kits are available and significantly cheaper than OEM replacement.
Owner tips & cautions
TipCheck the hydraulic fluid level in the trunk reservoir monthly. Catching a leak early prevents damage to the trunk lining and keeps the pump from running dry.
High Confidence890 reportsLast reported by owners Nov 2025Reviewed Mar 2026
On the 2004-2015 Mercedes-Benz SLK/SLC, the M271 four-cylinder's camshaft adjuster magnets (variable valve timing solenoids) commonly fail or become oil-fouled on R171 SLK200 Kompressor and R172 SLK250 models. A well-documented M271 defect is engine oil wicking up the solenoid connector into the wiring harness toward the ECU and O2 sensor. This is distinct from timing-chain/gear wear: the solenoid itself sticks or shorts, upsetting cam timing and triggering camshaft-position/correlation codes.
Check-engine light for camshaft position/correlation
Rough idle or hesitation
Oil in the solenoid connector / harness
Occasional hard start or reduced power
Fault code moves when magnets are swapped
How to Fix
Replace the camshaft adjuster magnet solenoids and fit Mercedes' updated oil-stop connector/harness (Oelstoppkabel, e.g. A2711502733) that resists oil migration; clean oil from the connector and harness. Because the adjuster still tends to seep, periodic replacement (roughly every 30,000-40,000 miles) is common, and more frequent oil changes slow sludge buildup. A quick diagnostic is swapping intake/exhaust magnets to see if the fault code follows the part.
What are the most common Mercedes-Benz SLK/SLC problems?
According to Au7o's analysis of 890+ owner reports, the 2012 Mercedes-Benz SLK/SLC has 2 documented issues. The most frequently reported are: Vario Roof Retractable Hardtop Hydraulic Leak, M271 Camshaft Adjuster (VVT) Magnet Solenoid Failure and Oil Intrusion. None are rated critical, but regular maintenance is recommended.
Is the Mercedes-Benz SLK/SLC reliable?
The 2012 Mercedes-Benz SLK/SLC has 2 known issues documented across 890+ owner reports. No issues are rated critical, suggesting generally good reliability. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common Mercedes-Benz SLK/SLC problems?
Repair costs for known Mercedes-Benz SLK/SLC issues range from $120 to $2,500, depending on the specific problem and whether you choose DIY or professional repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What is the 2005-2020 Mercedes-Benz SLK/SLC Vario Roof Retractable Hardtop Hydraulic Leak?
The Vario Roof retractable hardtop on both R171 and R172 SLK/SLC models develops hydraulic leaks at the cylinders, lines, and pump. The most common leak points are the roof lock cylinders and the main lift cylinders. Leaking hydraulic fluid drips into the trunk area and can damag… Repairs typically run $500-$2,500. Severity: medium.
What is the 2004-2015 Mercedes-Benz SLK/SLC M271 Camshaft Adjuster (VVT) Magnet Solenoid Failure and Oil Intrusion?
The M271 four-cylinder's camshaft adjuster magnets (variable valve timing solenoids) commonly fail or become oil-fouled on R171 SLK200 Kompressor and R172 SLK250 models. A well-documented M271 defect is engine oil wicking up the solenoid connector into the wiring harness toward t… Repairs typically run $120-$550. Severity: medium.
Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.
