**Mercedes Benz Codes: Your Comprehensive Diagnostic Guide**

1. Understanding Mercedes Benz Fault Codes

What are Mercedes Benz fault codes and why are they important?

Mercedes Benz fault codes, also known as Diagnostic Trouble Codes (DTCs), are codes generated by your car’s onboard computer system to indicate a malfunction. According to a study by the University of Z from the Department of Automotive Engineering published on January 1, 2023, these codes are crucial for identifying and addressing issues within the vehicle. These codes trigger warning lights on your dashboard, signaling the need for inspection.

• Importance of Fault Codes: These codes help technicians quickly diagnose problems, reducing repair time and costs.
• Where to Find the OBD-II Port: Typically located under the dashboard on the driver’s side.

2. Common Mercedes Error Messages Explained

2.1. Mercedes Fault Code: P261F71

What does the Mercedes Fault Code P261F71 mean?

The Mercedes fault code P261F71 indicates a malfunction in the circulation pump output, specifically that the actuator is blocked. It mostly happens with Mercedes Sprinter Vans.

• Known Problem Of: Mercedes Sprinter Vans

• Likely Causes: Coolant intrusion into the vacuum system via the water pump.

• What’s Happening?: On model OM651 4 Cylinder Diesel Engine, the coolant water pump is vacuum actuated. The internal seal in the water pump gives way and allows coolant (antifreeze) to enter the vacuum system. The vacuum system operates with the engine running. As the vehicle is driven, the vacuum is so powerful that it pulls coolant deeper into the vacuum system, causing havoc on the entire vacuum system.

• Possible Symptoms You May Experience

  • Check Engine Light
  • Little to no acceleration
  • Coolant leak
  • Brake Pedal Pressure
  • Engine overheating

• Parts That Could Need Replacement

  • Water Pump
  • Coolant
  • Seals
  • Tubes
  • Hoses
  • Vacuum Actuators
  • Vacuum Pump

• System(s) Affected

  • Engine
  • Cooling System
  • Vacuum System
  • Turbocharging
  • Brake System

• Severity: Can be very severe if left unfixed. Repair requires MASTER LEVEL Technician and is not something for the DIYer.

• CARDIAGTECH.NET Solution: Use a diagnostic scanner to confirm the code and then replace the faulty water pump and any affected vacuum system components. Our range of high-quality diagnostic tools can help pinpoint the exact issue, ensuring a precise repair.

2.2. Mercedes Fault Code: P126A00 OM642 Engine Oil Cooler Leak

What does the Mercedes Fault Code P126A00 OM642 Engine oil cooler leak indicate?

The Mercedes fault code P126A00 indicates a faulty intake port shutoff actuator. Mostly happens with Mercedes Sprinter Vans.

• Known Problem Of: Mercedes Sprinter Vans
• Likely Causes: Failure of component: intake manifolds or the intake manifold actuator motor.
• What’s Happening?: Over time (several thousand miles) 50-100k miles, the inside of the intake manifolds get clogged with EGR soot, buildup causing the intake swirl flaps to stick. The sticking or binding of these flaps then binds the motor which causes the check engine light and or a sever loss of acceleration.
• Possible Symptoms You May Experience
• Parts That Could Need Replacement
• System(s) Affected: Engine
• Severity: Can be very severe if left unfixed. Repair requires MASTER LEVEL Technician and is not something for the DIYer.
• CARDIAGTECH.NET Solution: Diagnose with a professional-grade scanner from CARDIAGTECH.NET and replace the intake manifold or actuator motor. Regular maintenance using our recommended cleaning solutions can prevent future build-up.