How To Read Mercedes Codes: A Comprehensive Guide
Decoding Mercedes codes is essential for maintaining your vehicle’s peak performance. At CARDIAGTECH.NET, we provide the expertise and tools necessary to accurately diagnose and resolve any issues your Mercedes may encounter. Master the art of reading Mercedes diagnostic codes, understand their meanings, and learn how to effectively troubleshoot common problems to keep your luxury vehicle running smoothly. Let us help you enhance your diagnostic capabilities and ensure your Mercedes receives the best possible care.
To assist you further, here is a comprehensive list of Mercedes-Benz fault codes, categorized by system:
5.1. P0400 Mercedes Fault Codes Meaning
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 |
5.2. P0500 Mercedes Fault Codes Meaning
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 |
5.3. P0600 Mercedes Fault Codes Meaning
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 |
5.4. P0700 Mercedes Fault Codes Meaning
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 |
5.5. P0800 Mercedes Fault Codes Meaning
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 |
5.6. P1000-P2000 Fault Codes Meaning
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 |
Alt Text: A detailed view of a Mercedes-Benz engine, highlighting the various components monitored by the vehicle’s diagnostic system.
5.7. Mercedes Body Fault Codes
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 |
5.8. Mercedes C-Level Fault Codes
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 lose memory(?) |
C1142 | ABS Lateral Acceleration Sensor Open/Shorted |
C1144 | AIRmatic: fault in component B7 (pressure sensor) |
C1200 | Stop Light Switch Open/Shorted/Implausible |
C1300 | Left Front Axle Solenoid Valve (Hold) (A7/3y6) Open/Shorted |
C1303 | Right Front Axle Solenoid Valve (Hold) Open/Shorted |
C1311 | Switchover Solenoid Valve (Release) Open/Shorted |
C1312 | Master Cylinder Switchover Valve |
C1401 | High Pressure Return Pump Circuit Open/Shorted; Will Not Shut Off |
C1501 | SPS P-Valve |
C1504 | BAS light, play in steering column causes steering angle sensor to lose memory(?) |
C1512 | Brakes Overheated |
C1600 | Temperature After Engine Is Turned OffU0001 High Speed CAN Communication Bus |
Alt Text: A close-up of Mercedes-Benz brakes, an essential system covered by C-level fault codes.
5.9. Mercedes U0 Codes
Mercedes Fault Code | Fault Code Meaning |
---|---|
U0001 | High Speed CAN Communication Bus |
U0002 | High Speed CAN Communication Bus Performance |
U0003 | High Speed CAN Communication Bus (+) open |
U0004 | High Speed CAN Communication Bus (+) low |
U0005 | High Speed CAN Communication Bus (+) high |
U0006 | High Speed CAN Communication Bus (-) open |
U0007 | High Speed CAN Communication Bus (-) low |
U0008 | High Speed CAN Communication Bus (-) high |
U0009 | High Speed CAN Communication Bus (-) shorted to Bus (+) |
U0010 | Medium Speed CAN Communication Bus |
U0011 | Medium Speed CAN Communication Bus Performance |
U0012 | Medium Speed CAN Communication Bus (+) open |
U0013 | Medium Speed CAN Communication Bus (+) low |
U0014 | Medium Speed CAN Communication Bus (+) high |
U0015 | Medium Speed CAN Communication Bus (-) open |
U0016 | Medium Speed CAN Communication Bus (-) low |
U0017 | Medium Speed CAN Communication Bus (-) high |
U0018 | Medium Speed CAN Communication Bus (-) shorted to Bus (+) |
U0019 | Low Speed CAN Communication Bus |
U0020 | Low Speed CAN Communication Bus Performance |
U0021 | Low Speed CAN Communication Bus (+) open |
U0022 | Low Speed CAN Communication Bus (+) low |
U0023 | Low Speed CAN Communication Bus (+) high |
U0024 | Low Speed CAN Communication Bus (-) open |
U0025 | Low Speed CAN Communication Bus (-) low |
U0026 | Low Speed CAN Communication Bus (-) high |
U0027 |