Mercedes Benz Fault Codes are diagnostic trouble codes that your vehicle’s onboard computer generates when it detects a malfunction in one of its many systems. Understanding these codes is the first step toward resolving the issue and getting your Mercedes back on the road. CAR-TOOL.EDU.VN offers comprehensive resources for decoding Mercedes fault codes and finding the right parts and tools for repairs. Accurate diagnostics, efficient repairs, and reduced downtime are some of the things you can look forward to.
Contents
- 1. Understanding Mercedes-Benz Fault Codes
- 1.1 What is a Fault Code?
- 1.2 How Fault Codes are Triggered
- 1.3 The Role of Onboard Diagnostics (OBD)
- 1.4 Decoding a Fault Code
- 1.5 Importance of Accurate Diagnosis
- 1.6 Resources for Fault Code Information
- 2. Common Mercedes-Benz Error Messages Explained
- 2.1 Mercedes Fault Code: P261F71
- 2.2 Mercedes Fault Code: P126A00 OM642 Engine Oil Cooler Leak
- 2.3 Comprehensive List of Mercedes Fault Codes
- 2.4 Example: P0400 Mercedes Fault Codes Meaning
- 2.5 Example: P0500 Mercedes Fault Codes Meaning
- 2.6 Example: P0600 Mercedes Fault Codes Meaning
- 2.7 Example: P0700 Mercedes Fault Codes Meaning
- 2.8 Example: P0800 Mercedes Fault Codes Meaning
- 2.9 Example: P1000-P2000 Mercedes Fault Codes Meaning
- 2.10 Body (B####) Fault Codes
- 2.11 C-Level Fault Codes
1. Understanding Mercedes-Benz Fault Codes
Mercedes-Benz fault codes, also known as Diagnostic Trouble Codes (DTCs), serve as error notifications pinpointing malfunctions within your vehicle’s systems. These codes are essential for diagnosing and addressing problems, thus ensuring your Mercedes-Benz operates smoothly. According to a study by the National Institute for Automotive Service Excellence (ASE), accurate interpretation of these codes can reduce diagnostic time by up to 40%.
1.1 What is a Fault Code?
A fault code is a standardized alphanumeric code used to identify a specific problem in a vehicle’s system. Modern Mercedes-Benz vehicles are equipped with numerous sensors and computer systems that continuously monitor performance. When a sensor detects a reading outside of the normal parameters, a fault code is generated and stored in the vehicle’s computer.
1.2 How Fault Codes are Triggered
Fault codes are triggered when a vehicle’s computer detects an issue with one or more of its systems. These systems can range from the engine and transmission to the brakes and emissions controls.
- Sensor Malfunctions: Faulty sensors can provide incorrect data, triggering fault codes.
- Electrical Issues: Short circuits, open circuits, and other electrical problems can cause fault codes to appear.
- Mechanical Failures: Issues such as a worn-out part or a malfunctioning component can trigger a fault code.
- Software Glitches: In some cases, software errors can lead to false fault codes.
1.3 The Role of Onboard Diagnostics (OBD)
Onboard Diagnostics (OBD) systems are crucial for monitoring vehicle performance and identifying potential issues. The OBD-II system, which is standard in most modern vehicles, provides a standardized interface for accessing fault codes. According to the Environmental Protection Agency (EPA), OBD-II systems have significantly reduced vehicle emissions by enabling timely detection and repair of emission-related problems.
1.4 Decoding a Fault Code
Mercedes-Benz fault codes typically consist of a letter followed by four numbers. Here’s a breakdown of what each part of the code signifies:
- First Character (Letter): Indicates the system where the fault occurred.
- P: Powertrain (engine, transmission)
- B: Body (airbags, central locking)
- C: Chassis (ABS, suspension)
- U: Network Communication (CAN bus)
- Second Character (Number): Specifies whether the code is generic (0) or manufacturer-specific (1).
- Third Character (Number): Indicates the specific subsystem.
- 1: Fuel and air metering
- 2: Fuel and air metering (injector circuit)
- 3: Ignition system or misfire
- 4: Auxiliary emission controls
- 5: Vehicle speed control and idle control system
- 6: Computer output circuit
- 7: Transmission
- 8: Transmission
- Fourth and Fifth Characters (Numbers): Indicate the specific fault within the subsystem.
For example, a code like “P0300” would indicate a generic (0) powertrain (P) fault related to ignition or misfire (3), specifically a random/multiple cylinder misfire (00).
1.5 Importance of Accurate Diagnosis
Accurate diagnosis is critical for resolving Mercedes-Benz fault codes efficiently and effectively. Misinterpreting a fault code can lead to unnecessary repairs and wasted time and money.
- Avoid Unnecessary Repairs: Accurate diagnosis ensures that only the faulty components are replaced.
- Save Time and Money: By pinpointing the exact problem, you can avoid spending time and money on incorrect solutions.
- Ensure Vehicle Safety: Addressing the root cause of the problem ensures that your vehicle operates safely and reliably.
1.6 Resources for Fault Code Information
Several resources are available to help diagnose Mercedes-Benz fault codes accurately.
- CAR-TOOL.EDU.VN: Provides detailed information on Mercedes-Benz fault codes, including possible causes and solutions.
- OBD-II Scanners: Diagnostic tools that can read and clear fault codes.
- Repair Manuals: Detailed guides that provide step-by-step instructions for diagnosing and repairing various issues.
- Online Forums: Online communities where Mercedes-Benz owners and mechanics share information and advice.
2. Common Mercedes-Benz Error Messages Explained
Understanding common Mercedes-Benz error messages is crucial for timely diagnosis and repair. These error messages can indicate a range of issues, from minor sensor malfunctions to significant mechanical failures.
2.1 Mercedes Fault Code: P261F71
- Fault Code Meaning: The output for the circulation pump has a malfunction. Actuator is blocked.
- 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 it pulls coolant (antifreeze) 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 a MASTER LEVEL Technician and is not something for the DIYer.
2.2 Mercedes Fault Code: P126A00 OM642 Engine Oil Cooler Leak
- Fault Code Meaning: Intake Port Shutoff Actuator is faulty.
- 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 gets 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 severe loss of acceleration.
- Possible Symptoms You May Experience: Check Engine Light, loss of acceleration, rough idling.
- Parts That Could Need Replacement: Intake manifold, intake manifold actuator motor.
- System(s) Affected: Engine.
- Severity: Can be very severe if left unfixed. Repair requires a MASTER LEVEL Technician and is not something for the DIYer.
2.3 Comprehensive List of Mercedes Fault Codes
Here’s an overview of some common Mercedes-Benz fault codes categorized by their prefix:
- P0400 Series: Relates to emission control systems, including issues with the exhaust gas recirculation (EGR) system.
- P0500 Series: Involves vehicle speed sensors and idle control systems.
- P0600 Series: Pertains to internal control module malfunctions and communication issues.
- P0700 Series: Addresses transmission control system malfunctions, gear ratio problems, and shift solenoid issues.
- P0800 Series: Deals with transmission-related issues, such as clutch position sensor malfunctions and four-wheel-drive switch circuit problems.
- P1000-P2000 Series: Includes a range of specific fault codes, such as electronic gear selector module defects and NOx trap efficiency issues.
- Body (B####) Codes: Relate to body control systems, including airbag malfunctions, air conditioning problems, and lighting issues.
- C#### Codes: Address chassis-related issues, such as ABS malfunctions, suspension problems, and brake system faults.
- U#### Codes: Indicate network communication issues, such as lost communication with various control modules.
2.4 Example: P0400 Mercedes Fault Codes Meaning
The P0400 series of fault codes relates to issues within the exhaust gas recirculation (EGR) system, which is crucial for reducing emissions. Here’s a detailed look at some of these codes:
| Mercedes Fault Code | Fault Code Meaning |
|---|---|
| P0466 | Purge Flow Sensor Circuit Range/Performance |
| P0467 | Purge Flow Sensor Circuit Low Input |
| P0468 | Purge Flow Sensor Circuit High Input |
| P0469 | Purge Flow Sensor Circuit Intermittent |
| P0470 | Exhaust Pressure Sensor Malfunction |
| P0471 | Exhaust Pressure Sensor Range/Performance |
| P0472 | Exhaust Pressure Sensor Low |
| P0473 | Exhaust Pressure Sensor High |
| P0474 | Exhaust Pressure Sensor Intermittent |
| P0475 | Exhaust Pressure Control Valve Malfunction |
| P0476 | Exhaust Pressure Control Valve Range/Performance |
| P0477 | Exhaust Pressure Control Valve Low |
| P0478 | Exhaust Pressure Control Valve High |
| P0479 | Exhaust Pressure Control Valve Intermittent |
| P0480 | Cooling Fan 1 Control Circuit Malfunction |
| P0481 | Cooling Fan 2 Control Circuit Malfunction |
| P0482 | Cooling Fan 3 Control Circuit Malfunction |
| P0483 | Cooling Fan Rationality Check Malfunction |
| P0484 | Cooling Fan Circuit Over Current |
| P0485 | Cooling Fan Power/Ground Circuit Malfunction |
2.5 Example: P0500 Mercedes Fault Codes Meaning
The P0500 series of fault codes involves the vehicle speed sensor (VSS) and idle control system. These codes can affect the vehicle’s performance and fuel efficiency.
| Mercedes Fault Code | Fault Code Meaning |
|---|---|
| P0500 | Vehicle Speed Sensor Malfunction |
| P0501 | Vehicle Speed Sensor Range/Performance |
| P0502 | Vehicle Speed Sensor Low Input |
| P0503 | Vehicle Speed Sensor Intermittent/Erratic/High |
| P0505 | Idle Control System Malfunction |
| P0506 | Idle Control System RPM Lower Than Expected |
| P0507 | Idle Control System RPM Higher Than Expected |
| P0510 | Closed Throttle Position Switch Malfunction |
| P0520 | Engine Oil Pressure Sensor/Switch Circuit Malfunction |
| P0521 | Engine Oil Pressure Sensor/Switch Circuit Range/Performance |
| P0522 | Engine Oil Pressure Sensor/Switch Circuit Low Voltage |
| P0523 | Engine Oil Pressure Sensor/Switch Circuit High Voltage |
| P0530 | A/C Refrigerant Pressure Sensor Circuit Malfunction |
| P0531 | A/C Refrigerant Pressure Sensor Circuit Range/Performance |
| P0532 | A/C Refrigerant Pressure Sensor Circuit Low Input |
| P0533 | A/C Refrigerant Pressure Sensor Circuit High Input |
| P0534 | Air Conditioner Refrigerant Charge Loss |
| P0550 | Power Steering Pressure Sensor Circuit Malfunction |
| P0551 | Power Steering Pressure Sensor Circuit Range/Performance |
| P0552 | Power Steering Pressure Sensor Circuit Low Input |
| P0553 | Power Steering Pressure Sensor Circuit High Input |
| P0554 | Power Steering Pressure Sensor Circuit Intermittent |
| P0560 | System Voltage Malfunction |
| P0561 | System Voltage Unstable |
| P0562 | System Voltage Low |
| P0563 | System Voltage High |
| P0565 | Cruise Control On Signal Malfunction |
| P0566 | Cruise Control Off Signal Malfunction |
| P0567 | Cruise Control Resume Signal Malfunction |
| P0568 | Cruise Control Set Signal Malfunction |
| P0569 | Cruise Control Coast Signal Malfunction |
| P0570 | Cruise Control Accel Signal Malfunction |
| P0571 | Cruise Control/Brake Switch A Circuit Malfunction |
| P0572 | Cruise Control/Brake Switch A Circuit Low |
| P0573 | Cruise Control/Brake Switch A Circuit High |
| P0574 | Cruise Control Related Malfunction |
| P0575 | Cruise Control Related Malfunction |
| P0576 | Cruise Control Related Malfunction |
| P0576 | Cruise Control Related Malfunction |
| P0578 | Cruise Control Related Malfunction |
| P0579 | Cruise Control Related Malfunction |
| P0580 | Cruise Control Related Malfunction |
2.6 Example: P0600 Mercedes Fault Codes Meaning
The P0600 series of fault codes focuses on the serial communication link and internal control module issues. These codes often indicate problems with the vehicle’s computer systems.
| Mercedes Fault Code | Fault Code Meaning |
|---|---|
| P0600 | Serial Communication Link Malfunction |
| P0601 | Internal Control Module Memory Check Sum Error |
| P0602 | Control Module Programming Error |
| P0603 | Internal Control Module Keep Alive Memory (KAM) Error |
| P0604 | Internal Control Module Random Access Memory (RAM) Error |
| P0605 | Internal Control Module Read Only Memory (ROM) Error |
| P0606 | PCM Processor Fault |
| P0608 | Control Module VSS Output “A” Malfunction |
| P0609 | Control Module VSS Output “B” Malfunction |
| P0620 | Generator Control Circuit Malfunction |
| P0621 | Generator Lamp “L” Control Circuit Malfunction |
| P0622 | Generator Field “F” Control Circuit Malfunction |
| P0650 | Malfunction Indicator Lamp (MIL) Control Circuit Malfunction |
| P0654 | Engine RPM Output Circuit Malfunction |
| P0655 | Engine Hot Lamp Output Control Circuit Malfunction |
| P0656 | Fuel Level Output Circuit Malfunction |
2.7 Example: P0700 Mercedes Fault Codes Meaning
The P0700 series of fault codes pertains to the transmission control system. These codes can indicate a variety of issues, including incorrect gear ratios, shift solenoid malfunctions, and temperature sensor problems.
| Mercedes Fault Code | Fault Code Meaning |
|---|---|
| P0700 | Transmission Control System Malfunction |
| P0701 | Transmission Control System Range/Performance |
| P0702 | Transmission Control System Electrical |
| P0703 | Torque Converter/Brake Switch B Circuit Malfunction |
| P0704 | Clutch Switch Input Circuit Malfunction |
| P0705 | Transmission Range Sensor Circuit malfunction (PRNDL Input) |
| P0706 | Transmission Range Sensor Circuit Range/Performance |
| P0707 | Transmission Range Sensor Circuit Low Input |
| P0708 | Transmission Range Sensor Circuit High Input |
| P0709 | Transmission Range Sensor Circuit Intermittent |
| P0710 | Transmission Fluid Temperature Sensor Circuit Malfunction |
| P0711 | Transmission Fluid Temperature Sensor Circuit Range/Performance |
| P0712 | Transmission Fluid Temperature Sensor Circuit Low Input |
| P0713 | Transmission Fluid Temperature Sensor Circuit High Input |
| P0714 | Transmission Fluid Temperature Sensor Circuit Intermittent |
| P0715 | Input/Turbine Speed Sensor Circuit Malfunction |
| P0716 | Input/Turbine Speed Sensor Circuit Range/Performance |
| P0717 | Input/Turbine Speed Sensor Circuit No Signal |
| P0718 | Input/Turbine Speed Sensor Circuit Intermittent |
| P0719 | Torque Converter/Brake Switch B Circuit Low |
| P0720 | Output Speed Sensor Circuit Malfunction |
| P0721 | Output Speed Sensor Range/Performance |
| P0722 | Output Speed Sensor No Signal |
| P0723 | Output Speed Sensor Intermittent |
| P0724 | Torque Converter/Brake Switch B Circuit High |
| P0725 | Engine Speed input Circuit Malfunction |
| P0726 | Engine Speed Input Circuit Range/Performance |
| P0727 | Engine Speed Input Circuit No Signal |
| P0728 | Engine Speed Input Circuit Intermittent |
| P0730 | Incorrect Gear Ratio |
| P0731 | Gear 1 Incorrect Ratio |
| P0732 | Gear 2 Incorrect Ratio |
| P0733 | Gear 3 Incorrect Ratio |
| P0734 | Gear 4 Incorrect Ratio |
| P0735 | Gear 5 Incorrect Ratio |
| P0736 | Reverse Incorrect Gear Ratio |
| P0740 | Torque Converter Clutch Circuit Malfuction |
| P0741 | Torque Converter Clutch Circuit Performance or Stuck Off |
| P0742 | Torque Converter Clutch Circuit Stuck On |
| P0743 | Torque Converter Clutch Circuit Electrical |
| P0744 | Torque Converter Clutch Circuit Intermittent |
| P0745 | Pressure Control Solenoid Malfunction |
| P0746 | Pressure Control Solenoid Performance or Stuck Off |
| P0747 | Pressure Control Solenoid Stuck On |
| P0748 | Pressure Control Solenoid Electrical |
| P0749 | Pressure Control Solenoid Intermittent |
| P0750 | Shift Solenoid A Malfunction |
| P0751 | Shift Solenoid A Performance or Stuck Off |
| P0752 | Shift Solenoid A Stuck On |
| P0753 | Shift Solenoid A Electrical |
| P0754 | Shift Solenoid A Intermittent |
| P0755 | Shift Solenoid B Malfunction |
| P0756 | Shift Solenoid B Performance or Stuck Off |
| P0757 | Shift Solenoid B Stuck On |
| P0758 | Shift Solenoid B Electrical |
| P0759 | Shift Solenoid B Intermittent |
| P0760 | Shift Solenoid C Malfunction |
| P0761 | Shift Solenoid C Performance or Stuck Off |
| P0762 | Shift Solenoid C Stuck On |
| P0763 | Shift Solenoid C Electrical |
| P0764 | Shift Solenoid C Intermittent |
| P0765 | Shift Solenoid D Malfunction |
| P0766 | Shift Solenoid D Performance or Stuck Off |
| P0767 | Shift Solenoid D Stuck On |
| P0768 | Shift Solenoid D Electrical |
| P0769 | Shift Solenoid D Intermittent |
| P0770 | Shift Solenoid E Malfunction |
| P0771 | Shift Solenoid E Performance or Stuck Off |
| P0772 | Shift Solenoid E Stuck On |
| P0773 | Shift Solenoid E Electrical |
| P0774 | Shift Solenoid E Intermittent |
| P0780 | Shift Malfunction |
| P0781 | 1-2 Shift Malfunction |
| P0782 | 2-3 Shift Malfunction |
| P0783 | 3-4 Shift Malfunction |
| P0784 | 4-5 Shift Malfunction |
| P0785 | Shift/Timing Solenoid Malfunction |
| P0786 | Shift/Timing Solenoid Range/Performance |
| P0787 | Shift/Timing Solenoid Low |
| P0788 | Shift/Timing Solenoid High |
| P0789 | Shift/Timing Solenoid Intermittent |
| P0790 | Normal/Performance Switch Circuit Malfunction |
2.8 Example: P0800 Mercedes Fault Codes Meaning
The P0800 series of fault codes is related to transmission control and clutch-related issues. These codes can indicate problems with the clutch position sensor, four-wheel-drive switch, and transmission fluid pressure.
| Mercedes Fault Code | Fault Code Meaning |
|---|---|
| P0801 | Reverse Inhibit Control Circuit Malfunction |
| P0803 | 1-4 Upshift (Skip Shift) Solenoid Control Circuit Malfunction |
| P0804 | 1-4 Upshift (Skip Shift) Lamp Control Circuit Malfunction |
| P0805 | Clutch Position Sensor Circuit Malfunction |
| P0806 | Clutch Position Sensor Circuit Range/Performance |
| P0807 | Clutch Position Sensor Circuit Low |
| P0808 | Clutch Position Sensor Circuit High |
| P0809 | Clutch Position Sensor Circuit Intermittent Ckt |
| P0810 | Clutch Position Control Malfunction |
| P0811 | Clutch Slippage Excessive |
| P0812 | Reverse Input Circuit Malfunction |
| P0813 | Reverse Output Circuit Malfunction |
| P0814 | Trans Range Display Circuit Malfunction |
| P0815 | Upshift Switch Circuit Malfunction |
| P0816 | Downshift Switch Circuit Malfunction |
| P0817 | Starter Disable Circuit |
| P0818 | Driveline Disconn. Switch Input |
| P0820 | Gear Lever X-Y Sensor Circuit |
| P0821 | Gear Lever X Sensor Circuit |
| P0822 | Gear Lever Y Sensor Circuit |
| P0823 | Gear Lever X Sensor Circuit Intermittent Ckt |
| P0824 | Gear Lever Y Sensor Circuit Intermittent Ckt |
| P0830 | Clutch Position Switch A Circuit Malfunction |
| P0831 | Clutch Position Switch A Circuit Low |
| P0832 | Clutch Position Switch A Circuit High |
| P0833 | Clutch Position Switch B Circuit Malfunction |
| P0834 | Clutch Position Switch B Circuit Low |
| P0835 | Clutch Position Switch B Circuit High |
| P0836 | 4 Wheel Drive Switch Circuit Malfunction |
| P0837 | 4 Wheel Drive Switch CKT Range/Perf |
| P0838 | 4 Wheel Drive Switch Circuit Low |
| P0839 | 4 Wheel Drive Switch Circuit High |
| P0840 | Trans Fluid Press Sensor/Switch A Circuit Malfunction |
| P0841 | Trans Fluid Press Sensor/Switch A CKT Range/Perf |
| P0842 | Trans Fluid Press Sensor/Switch A Circuit Low |
| P0843 | Trans Fluid Press Sensor/Switch A Circuit High |
| P0844 | Trans Fluid Press Sensor/Switch A CKT Intermittent |
| P0845 | Trans Fluid Press Sensor/Switch B Circuit Malfunction |
| P0846 | Trans Fluid Press Sensor/Switch B CKT Range/Perf |
| P0847 | Trans Fluid Press Sensor/Switch B Circuit Low |
| P0848 | Trans Fluid Press Sensor/Switch B Circuit High |
| P0849 | Trans Fluid Press Sensor/Switch B CKT Intermittent |
2.9 Example: P1000-P2000 Mercedes Fault Codes Meaning
The P1000-P2000 series of fault codes includes a variety of specific issues, ranging from electronic gear selector module defects to exhaust gas temperature sensor problems.
| Mercedes Fault Code | Fault Code Meaning |
|---|---|
| P1000 | Electronic Gear Selector Module: Defective N15/5 |
| P1228 | Yet unknown code on 1997 C 220 CDI |
| P1386 | Knock control |
| P1570 | Intermittant No-Start Immobiliser Module |
| P1747 | Electronic Gear Selector Module: Defective Interaction of CAN with control unit A1(instrument cluster) |
| P1750 | Electronic Gear Selector Module: Very low control unit supply voltage |
| P1832 | Electronic Gear Selector Module: SHORT in circuit N15/5 output stage |
| P1910 | Electronic Gear Selector Module: Control Unit over voltage |
| P1912 | Electronic Gear Selector Module: Weak touch push button voltage |
| P2000 | NOx Trap Efficiency Below Threshold (Bank 1) |
| P2001 | NOx Trap Efficiency Below Threshold (Bank 2) |
| P2003 | Particulate Trap Efficiency Below Threshold (Bank 1) |
| P2004 | Particulate Trap Efficiency Below Threshold (Bank 2) |
| P2031 | Exhaust Gas Temperature Sensor Circuit (Bank 1 Sensor 2) |
| P2032 | Exhaust Gas Temperature Sensor Circuit Low (Bank 1 Sensor 2) |
| P2033 | Exhaust Gas Temperature Sensor Circuit High (Bank 1 Sensor 2) |
| P2080 | Exhaust Gas Temperature Sensor Circuit Range/Performance (Bank 1 Sensor 1) |
| P2081 | Exhaust Gas Temperature Sensor Circuit intermittant (Bank 1 Sensor 1) |
| P2100 | Throttle Actuator Control Motor Circuit/Open |
| P2101 | Throttle Actuator Control Motor Circuit Range/Performance |
| P2208 | Transmission: The speed of Y3/6n2 to Y3/6n3 is excessive |
2.10 Body (B####) Fault Codes
The Body (B####) series of fault codes relates to various systems within the vehicle’s body, including airbags, central locking, and air conditioning.
| Mercedes Fault Code | Fault Code Meaning |
|---|---|
| B1000 | HRA Headlamp range adjustment: Supply voltage of the control unit is too low (undervoltage) |
| B1004 | LCP Lower Control Panel: Control unit does not match vehicle type |
| B1056 | Automatic Air Conditioning: Problem in CAN communication with control unit DCM-RL |
| B1201 | Electric seat adjustment front left: Hall sensor front height M27m3 |
| B1213 | If seat memory installed: ext right rearview mirror voltage faulty |
| B1214 | If seat memory installed: ext right rearview mirror voltage faulty |
| B1226 | In-car temperature sensor (B10/4) |
| B1227 | Outside temperature indicator temp sensor (014) |
| B1128 | Heater core temperature (B10/1) |
| B1229 | Heater core temperature (B10/1) |
| B1230 | Evaporator temperature sensor (B10/6) |
| B1231 | ECT sensor (B11/4) |
| B1232 | Refrigerant pressure sensor (B12) |
| B1233 | Refrigerant temperature sensor (B12/1) |
| B1234 | Sun sensor (B32) |
| B1235 | Emissions sensor (B31) |
| B1241 | Refrigerant Fill |
| B1246 | PTS Parktronic: A42b1 (left outer sensor, front bumper) The plug connection has poor contact or is loose, or the sensor or cable is faulty |
| B1310 | Left/Window airbag sensor is defective |
| B1315 | Problem in Front passenger child seat recognition |
| B1416 | Coolant circulation pump (M13) |
| B1417 | Duovalve (Y21y1), left |
| B1418 | Duovalve (Y21y2), right |
| B1419 | Electromagnetic clutch (A9k1) |
| B1420 | Idle speed increase |
| B1421 | Pulse module (N05) |
| B1422 | Series interface (K1) connection to instrument cluster (A1) |
| B1423 | Switchover valve block (Y11) |
| B1424 | Activated charcoal filler actuator (A32m2) open |
| B1425 | Activated charcoal filler actuator (A32m2) closed |
| B1432 | Non-USA DTC |
| B1459 | Series interface (K2) connection to instrument cluster (A1) |
| B1462 | Wide open throttle (WOT) position signal diesel engines |
| B1476 | Airbag malfunction indicator and warning lamp is defective |
| B1481 | HRA: Part E2m1 (Right headlamp range adjustment motor) has short to ground |
| B1489 | HRA: Part E2m1 (Right headlamp range adjustment motor) has open or short to positive |
| B1492 | HRA: Part E1m1 (Left headlamp range adjustement motor) has short to positive/td> |
| B1617 | Part E19/1 (Left license plate lamp) is defective |
| B1618 | Part E19/2 (Right license plate lamp) is defective |
| B1628 | Part E2e5 (Turn signal lamp) in module E2 (Right front headlamp unit) is defective. |
| B1703 | Intermittant No Start in AAM Immobiliser Module |
| B1729 | PSE Pneumatic system doorlock Control Module A37 |
| B1736 | Navigation system’s CD Player: Check General CD, Check CD data block, Flimsy CD data |
| B1768 | Faulty open data flap limit switch (0025) Front flap |
| B1773 | HRA: Zero position programming has not yet been carried out or is not possible |
| B1850 | Electric seat adjustment front right: CAN communication interrupted with DCMC1000 Traction System Control Module |
2.11 C-Level Fault Codes
The C-Level series of fault codes addresses chassis-related issues, such as ABS malfunctions, suspension problems, and brake system faults.
| Mercedes Fault Code | Fault Code Meaning |
|---|---|
| C1010 | Battery Voltage Low |
| C1011 | ASR/ETS/ESP Circuit Open or Shorted |
| C1012 | Battery Voltage High |
| C1020 | CAN Communication Fault |
| C1021 | CAN Communication With EA/CC/ISC Control Module Interrupted |
| C1024 | CAN Communication With Engine Control Module Interrupted |
| C1025 | CAN Communication BAS communication with ESP control unit faulty |
| C1100 | Left Front Axle VSS Circuit Fault |
| C1101 | Right Front Axle VSS Circuit Fault |
| C1102 | ETS/ASR, ABS Left Axle VSS Circuit Fault |
| C1103 | Right Rear Axle VSS Circuit Fault |
| C1121 | AIRmatic: fault in component B22/3 (level sensor) |
| C1122 | AIRmatic: fault in component B22/4 (level sensor) |
| C1123 | AIRmatic: fault in component B22/6 (level sensor) |
| C1132 | AIRmatic: fault in component B22/8 (level sensor) |
| C1133 | AIRmatic: fault in component B22/9 (level sensor) |
| C1135 | AIRmatic: fault in component B22/3 (level sensor) |
| C1140 | BAS light, play in steering column causes steering angle sensor to |
