2012 Mercedes-Benz Coraza S2

The 2012 Mercedes-Benz C-Class coupe, specifically the C250, offered a blend of luxury and sportiness. The C250 came standard with a 1.8-liter turbocharged inline-4 engine producing around 201 horsepower and 229 lb-ft of torque, paired with a 7-speed automatic transmission (7G-Tronic). Other engine options for the 2012 C-Class included a 3.5L V6 (C300/C350) and a high-performance AMG variant. Owners generally appreciate the C-Class for its elegant styling, comfortable ride, and refined interior. However, some common complaints revolve around reliability issues, particularly with the electrical system and certain engine components.

Engine

1.8L Turbocharged Inline-4 (C250)

• High-Pressure Fuel Pump Failure
  • Description/Symptoms: Engine stalling, rough idling, extended cranking time, fuel smell, check engine light.
  • Solution: Replace the high-pressure fuel pump.
  • Estimated Cost to Fix: $700 - $1,200+
  • Recalls: None Found
• Timing Chain Tensioner Failure
  • Description/Symptoms: Rattling noise upon startup, especially in cold weather. Can lead to timing chain skipping and major engine damage if left unaddressed.
  • Solution: Replace the timing chain, tensioner, and associated guides.
  • Estimated Cost to Fix: $1,500 - $3,000+
  • Recalls: None Found
• Camshaft Adjuster Solenoid Issues
  • Description/Symptoms: Check engine light, rough idling, reduced engine performance, poor fuel economy.
  • Solution: Replace faulty camshaft adjuster solenoid(s).
  • Estimated Cost to Fix: $300 - $600+
  • Recalls: None Found

3.5L V6 (C300/C350)

• Camshaft Adjuster Magnet Failure
  • Description/Symptoms: Check engine light illuminated, rough idling, reduced power, and potential engine misfires.
  • Solution: Replacement of the faulty camshaft adjuster magnet.
  • Estimated Cost to Fix: $500 - $800+
  • Recalls: None Found

Transmission

7G-Tronic (7-Speed Automatic)

• Torque Converter Lock-Up Clutch Failure
  • Description/Symptoms: Shuddering or vibration during light acceleration, particularly at lower speeds. Can cause the transmission to overheat.
  • Solution: Replace the torque converter. In some cases, a transmission flush and fluid change may temporarily alleviate the issue.
  • Estimated Cost to Fix: $1,500 - $3,000+
  • Recalls: None Found
• Valve Body Issues
  • Description/Symptoms: Harsh shifting, delayed engagement, slipping between gears, or failure to shift at all.
  • Solution: Replace or rebuild the valve body.
  • Estimated Cost to Fix: $800 - $2,000+
  • Recalls: None Found

Suspension

• Front Control Arm Bushing Failure
  • Description/Symptoms: Clunking or squeaking noise when driving over bumps, vague steering, uneven tire wear.
  • Solution: Replace the worn control arm bushings or the entire control arm assembly.
  • Estimated Cost to Fix: $300 - $800+ per side
  • Recalls: None Found
• Rear Air Suspension Issues (If Equipped)
  • Description/Symptoms: Vehicle sagging on one side, air compressor running excessively, warning lights on the dashboard.
  • Solution: Inspect and repair or replace the air struts, air compressor, or air lines.
  • Estimated Cost to Fix: $800 - $2,000+ per strut, $500-$1,000+ for the compressor
  • Recalls: None Found

Electrical

• EIS (Electronic Ignition Switch) Failure
  • Description/Symptoms: Key not recognized, inability to start the vehicle, steering wheel lock malfunction.
  • Solution: Replace the EIS module and reprogram it to the vehicle.
  • Estimated Cost to Fix: $800 - $1,500+
  • Recalls: None Found
• SAM (Signal Acquisition Module) Issues
  • Description/Symptoms: Malfunctioning lights, wipers, or other electrical accessories. Can also cause communication errors with other control modules.
  • Solution: Replace the faulty SAM module and reprogram it.
  • Estimated Cost to Fix: $500 - $1,200+
  • Recalls: None Found
• Battery Drain
  • Description/Symptoms: Vehicle battery frequently dying, even after short periods of inactivity.
  • Solution: Diagnose and repair the source of the parasitic drain. Common culprits include faulty door lock actuators, seat modules, or aftermarket electronics.
  • Estimated Cost to Fix: $100 - $500+ (depending on the cause)
  • Recalls: None Found

Exterior

• Sunroof Issues
  • Description/Symptoms: Sunroof not opening or closing properly, unusual noises during operation, water leaks.
  • Solution: Clean and lubricate the sunroof tracks and mechanism. In more severe cases, the sunroof motor or entire assembly may need to be replaced.
  • Estimated Cost to Fix: $100 - $1,000+
  • Recalls: None Found

Interior

• Center Console Control Knob Failure
  • Description/Symptoms: The Comand system control knob becomes unresponsive or erratic.
  • Solution: Replace the center console control knob assembly.
  • Estimated Cost to Fix: $300 - $600+
  • Recalls: None Found
• Heater Core Leak
  • Description/Symptoms: Sweet coolant smell in the cabin, fogging of the windshield, coolant loss.
  • Solution: Replace the heater core. This is a labor-intensive job.
  • Estimated Cost to Fix: $1,000 - $2,000+
  • Recalls: None Found

Summary

The 2012 Mercedes-Benz C-Class can be a rewarding vehicle to own, but it’s essential to be aware of potential issues. Electrical problems and engine issues, particularly with the 1.8L turbo and the 7G-Tronic transmission, are common. Repair costs can range from a few hundred dollars for minor fixes to several thousand dollars for major repairs like timing chain replacement or transmission overhaul. Potential buyers should have a pre-purchase inspection done to identify any existing or impending problems and budget accordingly for maintenance and repairs.