Mercedes W212 Fault Codes List: Your Ultimate Guide
Decoding your Mercedes W212 fault codes can be daunting, but CARDIAGTECH.NET is here to empower you with the knowledge and tools you need. We’ll provide a comprehensive Mercedes W212 diagnostic trouble codes list, common problems, and how to troubleshoot them effectively. Equip yourself with the right resources for Mercedes diagnostics, auto repair tools and automotive diagnostic equipment, enhancing your vehicle maintenance.
1. Understanding Mercedes-Benz W212 Fault Codes
Fault codes, or Diagnostic Trouble Codes (DTCs), are generated by your Mercedes-Benz W212’s onboard computer when it detects a malfunction. These codes serve as clues, directing technicians to the source of the problem. Ignoring these warning signs can lead to more extensive and expensive repairs down the line.
1.1. What Triggers a Fault Code?
The sophisticated network of sensors and systems in your W212 constantly monitors performance. When a component deviates from its expected parameters, a fault code is logged. Here are some common triggers:
- Sensor Malfunctions: Faulty sensors provide incorrect data, leading to inaccurate readings and codes.
- Electrical Issues: Wiring problems, shorts, or open circuits can disrupt the flow of information, generating errors.
- Mechanical Failures: Issues with components like the engine, transmission, or brakes can trigger related codes.
- Software Glitches: Occasionally, software bugs can cause false codes or misinterpret data.
1.2. The Importance of Accurate Diagnosis
While a fault code indicates a problem area, it doesn’t pinpoint the exact cause. A thorough diagnostic process is crucial to identify the root of the issue. Relying solely on the code can lead to misdiagnosis and unnecessary repairs.
2. Accessing Mercedes W212 Fault Codes
There are several ways to access the fault codes stored in your Mercedes W212’s computer:
2.1. Using an OBD-II Scanner
An OBD-II (On-Board Diagnostics II) scanner is a device that plugs into your car’s diagnostic port, typically located under the dashboard. It allows you to read and clear fault codes.
- Basic Scanners: These provide basic code reading capabilities.
- Advanced Scanners: These offer more features, such as live data streaming, component testing, and bidirectional control.
For Mercedes-Benz vehicles, it’s beneficial to invest in a scanner that supports manufacturer-specific codes. These codes provide more detailed information compared to generic OBD-II codes.
2.2. Professional Diagnostic Services
Taking your W212 to a qualified Mercedes-Benz technician is always a reliable option. They have specialized diagnostic tools and expertise to accurately diagnose and repair complex issues. Many independent shops also specialize in European vehicles and offer similar services.
3. Common Mercedes W212 Fault Codes and Their Meanings
Understanding the meaning of fault codes is the first step towards effective troubleshooting. Here’s a breakdown of some common codes you might encounter:
3.1. Powertrain (P-Codes)
These codes relate to the engine, transmission, and related systems.
| Code | Description | Possible Causes |
|---|---|---|
| P0016 | Crankshaft Position – Camshaft Position Correlation (Bank 1, Sensor A) | Misaligned timing, faulty camshaft or crankshaft sensor, timing chain stretch. |
| P0171 | System Too Lean (Bank 1) | Vacuum leaks, faulty MAF sensor, fuel pump issues, clogged fuel filter, faulty oxygen sensor. |
| P0300 | Random Misfire Detected | Faulty spark plugs, ignition coils, fuel injectors, vacuum leaks, low compression. |
| P0400 | Exhaust Gas Recirculation Flow Malfunction | Faulty EGR valve, clogged EGR passages, vacuum leaks in EGR system, faulty differential pressure sensor. |
| P0715 | Input/Turbine Speed Sensor Circuit Malfunction | Faulty input speed sensor, wiring problems, transmission issues. |
| P2006 | Intake Manifold Runner Control Stuck Closed (Bank 1) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2007 | Intake Manifold Runner Control Stuck Closed (Bank 2) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2008 | Intake Manifold Runner Control Circuit/Open (Bank 1) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2009 | Intake Manifold Runner Control Circuit/Open (Bank 2) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2010 | Intake Manifold Runner Control Circuit Short to Ground (Bank 1) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2011 | Intake Manifold Runner Control Circuit Short to Ground (Bank 2) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2012 | Intake Manifold Runner Control Circuit Short to Voltage (Bank 1) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2013 | Intake Manifold Runner Control Circuit Short to Voltage (Bank 2) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2014 | Intake Manifold Runner Position Sensor/Switch Circuit (Bank 1) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2015 | Intake Manifold Runner Position Sensor/Switch Circuit Range/Performance (Bank 1) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2016 | Intake Manifold Runner Position Sensor/Switch Circuit Low (Bank 1) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2017 | Intake Manifold Runner Position Sensor/Switch Circuit High (Bank 1) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
| P2018 | Intake Manifold Runner Position Sensor/Switch Circuit Intermittent/Erratic (Bank 1) | Faulty intake manifold runner control valve, linkage problems, carbon buildup in the intake manifold. |
3.2. Chassis (C-Codes)
These codes pertain to systems like ABS, ESP, and suspension.
| Code | Description | Possible Causes |
|---|---|---|
| C1000 | ABS Control Module Fault | Faulty ABS control module, wiring problems, hydraulic unit issues. |
| C1100 | Left Front Wheel Speed Sensor Circuit Malfunction | Faulty wheel speed sensor, wiring problems, ABS control module issue. |
| C1200 | Stop Light Switch Plausibility Failure | Faulty brake light switch, wiring problems, ABS control module issue. |
| C1401 | High-Pressure Return Pump Circuit Open/Shorted; Will Not Shut Off | Faulty high-pressure pump, wiring problems, ABS control module issue. |
| C1504 | BAS light, play in steering column causes steering angle sensor to lose memory. | Defective steering angle sensor, wiring issues, or problems within the Electronic Stability Program (ESP) system. |
3.3. Body (B-Codes)
These codes relate to interior and exterior components like lights, windows, and seats.
| Code | Description | Possible Causes |
|---|---|---|
| B1000 | Control unit N10/1 (Central gateway control unit) is defective. | Internal failure of the central gateway control unit, software corruption, or issues with the CAN bus network. |
| B1001 | Fault in component N70 (Upper control panel control unit). | Malfunction in the upper control panel, which can affect various functions such as lighting, sunroof operation, or the display of information. |
| B1004 | LCP Lower Control Panel: Control unit does not match vehicle type | Configuration problem or incompatibility between the lower control panel and the vehicle’s system, often occurring after a replacement or software update where the panel was not properly coded to the vehicle. |
| B1056 | Automatic Air Conditioning: Problem in CAN communication with control unit DCM-RL | Communication fault with the rear left door control module, which can disrupt functions such as the operation of windows, door locks, or mirror adjustments on the rear left door. |
| B1201 | Electric seat adjustment front left: Hall sensor front height M27m3 | Problems with the front height adjustment motor or its associated Hall sensor for the driver’s seat, potentially causing the seat to not adjust correctly or at all. |
| B1213 | If seat memory installed: ext right rearview mirror voltage faulty | Power supply issue or fault in the external right rearview mirror, particularly in vehicles equipped with seat memory, affecting the mirror’s ability to adjust or operate correctly. |
| B1214 | If seat memory installed: ext right rearview mirror voltage faulty | Same as B1213, another instance or specific issue related to the external right rearview mirror, especially in models with seat memory, indicating voltage-related problems. |
| B1226 | In-car temperature sensor (B10/4) | Malfunction of the in-car temperature sensor, which is used by the climate control system to regulate cabin temperature, potentially leading to inaccurate temperature readings and inefficient heating or cooling. |
| B1227 | Outside temperature indicator temp sensor (014) | Failure of the outside temperature sensor, affecting the accuracy of the temperature displayed on the dashboard, which can influence the automatic climate control settings and driver information. |
| B1128 | Heater core temperature (B10/1) | Problem with the temperature sensor in the heater core, impacting the system’s ability to measure and regulate the heat output, possibly leading to insufficient heating or incorrect temperature control. |
| B1229 | Heater core temperature (B10/1) | Same as B1128, indicating a recurring or additional issue related to the heater core temperature sensor that affects heating system performance. |
| B1230 | Evaporator temperature sensor (B10/6) | Malfunction of the evaporator temperature sensor, which is crucial for preventing the evaporator from freezing up during air conditioning operation, potentially leading to reduced cooling efficiency or system damage. |
| B1231 | ECT sensor (B11/4) | Failure of the Engine Coolant Temperature (ECT) sensor, which is vital for monitoring engine temperature to control fuel injection and ignition timing, potentially resulting in poor engine performance, overheating, or incorrect diagnostic information. |
| B1232 | Refrigerant pressure sensor (B12) | Issues with the refrigerant pressure sensor in the air conditioning system, which monitors the pressure of the refrigerant to ensure proper system operation and prevent damage from over- or under-pressurization. This can lead to inefficient cooling or system shutdown. |
| B1233 | Refrigerant temperature sensor (B12/1) | Malfunction of the refrigerant temperature sensor, which is used to optimize the performance of the air conditioning system, potentially leading to inefficient cooling, system damage, or incorrect diagnostic information. |
| B1234 | Sun sensor (B32) | Problem with the sun sensor, which measures the intensity of sunlight to adjust the climate control system automatically, potentially causing the system to not compensate correctly for solar heat and affecting cabin comfort. |
| B1235 | Emissions sensor (B31) | Failure of the emissions sensor, which monitors exhaust gases to ensure compliance with environmental regulations. This can trigger warning lights and potentially affect the vehicle’s ability to pass emissions tests. |
| B1241 | Refrigerant Fill | Low refrigerant level in the air conditioning system, indicating a leak or insufficient refrigerant, leading to reduced cooling performance and potential damage to the compressor if not addressed. |
| 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 | Faulty or disconnected parking sensor on the front bumper, specifically the left outer sensor, which can disrupt the Parktronic system’s ability to detect obstacles, leading to inaccurate or non-existent warnings while parking. |
| B1310 | Left/Window airbag sensor is defective | Malfunction in the left or window airbag sensor, potentially compromising the airbag system’s ability to deploy properly in the event of a collision, affecting passenger safety. |
| B1315 | Problem in Front passenger child seat recognition | Issues with the child seat recognition system in the front passenger seat, which can prevent the airbag from deactivating when a child seat is present, posing a risk to the child in case of an accident. |
| B1416 | Coolant circulation pump (M13) | Failure of the coolant circulation pump, which is critical for maintaining the engine’s operating temperature and preventing overheating, especially in turbocharged engines. |
| B1417 | Duovalve (Y21y1), left | Malfunction of the left duovalve in the climate control system, which regulates the flow of coolant to the heater core, potentially leading to inefficient heating or incorrect temperature control on the driver’s side. |
| B1418 | Duovalve (Y21y2), right | Malfunction of the right duovalve in the climate control system, affecting the passenger side’s heating performance. |
| B1419 | Electromagnetic clutch (A9k1) | Issues with the electromagnetic clutch in the air conditioning compressor, which engages and disengages the compressor to regulate cooling, potentially leading to a lack of cooling or inefficient operation of the AC system. |
| B1420 | Idle speed increase | A command for the engine control unit (ECU) to increase the idle speed, often due to compensating for additional loads such as the air conditioning compressor or to prevent stalling. Can indicate issues with idle control or load management systems. |
| B1421 | Pulse module (N05) | Malfunction of the pulse module, which is part of the climate control system. |
| B1422 | Series interface (K1) connection to instrument cluster (A1) | Communication issue between the climate control system and the instrument cluster, which can disrupt the display of temperature settings or other climate control information on the dashboard. |
| B1423 | Switchover valve block (Y11) | Problems with the switchover valve block, which is part of the climate control system. |
| B1424 | Activated charcoal filler actuator (A32m2) open | Indicates a problem with the activated charcoal canister system used to capture fuel vapors from the fuel tank. An open circuit or a stuck actuator can lead to improper venting, affecting fuel efficiency and emissions. |
| B1425 | Activated charcoal filler actuator (A32m2) closed | Similar to B1424 but indicates the actuator is stuck in the closed position, which can also lead to improper venting, causing pressure build-up in the fuel system or affecting engine performance. |
| B1432 | Non-USA DTC | This code indicates that the Diagnostic Trouble Code (DTC) is specific to models not sold in the USA. It could relate to various systems and may require a scan tool with region-specific diagnostics capabilities to interpret accurately. |
| B1459 | Series interface (K2) connection to instrument cluster (A1) | Similar to B1422, this code points to a communication issue. |
| B1462 | Wide open throttle (WOT) position signal diesel engines | Indicates that the wide-open throttle signal isn’t being correctly communicated. |
| B1476 | Airbag malfunction indicator and warning lamp is defective | This code indicates that the airbag malfunction indicator or warning lamp is not functioning correctly. This could be due to a burnt-out bulb, a wiring issue, or a fault within the instrument cluster itself, potentially compromising the driver’s ability to be warned of airbag system malfunctions. |
| B1481 | HRA: Part E2m1 (Right headlamp range adjustment motor) has short to ground | Indicates a short circuit in the right headlamp range adjustment motor, which can affect the ability to adjust the height of the headlamp beam, potentially reducing visibility and posing a safety risk. |
| B1489 | HRA: Part E2m1 (Right headlamp range adjustment motor) has open or short to positive | Similar to B1481, but specifies either an open circuit or a short to a positive voltage in the right headlamp range adjustment motor. |
| B1492 | HRA: Part E1m1 (Left headlamp range adjustement motor) has short to positive/td> | Indicates a short circuit to a positive voltage in the left headlamp range adjustment motor. |
| B1617 | Part E19/1 (Left license plate lamp) is defective | Indicates that the left license plate lamp is not functioning. |
| B1618 | Part E19/2 (Right license plate lamp) is defective | Indicates that the right license plate lamp is not functioning. |
| B1628 | Part E2e5 (Turn signal lamp) in module E2 (Right front headlamp unit) is defective. | Indicates that the turn signal lamp within the right front headlamp assembly is malfunctioning. |
| B1703 | Intermittant No Start in AAM Immobiliser Module | Indicates an intermittent fault within the immobilizer system. |
| B1729 | PSE Pneumatic system doorlock Control Module A37 | Issues with the PSE module which controls the pneumatic door locking system, possibly leading to malfunctions in locking or unlocking doors. |
| B1736 | Navigation system’s CD Player: Check General CD, Check CD data block, Flimsy CD data | Indicates a problem with the navigation system’s CD player. |
| B1768 | Faulty open data flap limit switch (0025) Front flap | Indicates an issue with the limit switch for the front data flap. |
| B1773 | HRA: Zero position programming has not yet been carried out or is not possible | This code indicates that the headlamp range adjustment (HRA) system has not been properly calibrated or that the calibration process failed. |
| B1850 | Electric seat adjustment front right: CAN communication interrupted with DCMC1000 Traction System Control Module | Indicates a disruption in the Controller Area Network (CAN) communication between the right front electric seat adjustment system and the Dynamic Stability Control Module (DCMC1000). |
3.4. Communication/Network (U-Codes)
These codes relate to communication issues between different control modules in the vehicle.
| Code | Description | Possible Causes |
|---|---|---|
| U0001 | High Speed CAN Communication Bus | A general fault indicating an issue with the high-speed Controller Area Network (CAN) bus, which is crucial for communication between various control modules. This can result in a wide range of symptoms affecting different vehicle systems. |
| U0002 | High Speed CAN Communication Bus Performance | The high-speed CAN bus is not performing optimally, potentially causing delays or errors in communication between modules. This can lead to intermittent issues or degraded performance in multiple systems. |
| U0003 | High Speed CAN Communication Bus (+) open | Indicates an open circuit on the positive wire of the high-speed CAN bus, disrupting communication. |
| U0004 | High Speed CAN Communication Bus (+) low | The voltage on the positive wire of the high-speed CAN bus is lower than expected, which can prevent modules from communicating effectively. |
| U0005 | High Speed CAN Communication Bus (+) high | The voltage on the positive wire of the high-speed CAN bus is higher than expected. |
| U0006 | High Speed CAN Communication Bus (-) open | An open circuit on the negative wire of the high-speed CAN bus, similar to U0003 but on the opposite wire. |
| U0007 | High Speed CAN Communication Bus (-) low | The voltage on the negative wire of the high-speed CAN bus is lower than expected. |
| U0008 | High Speed CAN Communication Bus (-) high | The voltage on the negative wire of the high-speed CAN bus is higher than expected. |
| U0009 | High Speed CAN Communication Bus (-) shorted to Bus (+) | A short circuit between the positive and negative wires of the high-speed CAN bus, which can completely disrupt communication. |
| U0010 | Medium Speed CAN Communication Bus | A general fault indicating an issue with the medium-speed CAN bus. |
| U0011 | Medium Speed CAN Communication Bus Performance | The medium-speed CAN bus is not performing optimally. |
| U0012 | Medium Speed CAN Communication Bus (+) open | An open circuit on the positive wire of the medium-speed CAN bus. |
| U0013 | Medium Speed CAN Communication Bus (+) low | The voltage on the positive wire of the medium-speed CAN bus is lower than expected. |
| U0014 | Medium Speed CAN Communication Bus (+) high | The voltage on the positive wire of the medium-speed CAN bus is higher than expected. |
| U0015 | Medium Speed CAN Communication Bus (-) open | An open circuit on the negative wire of the medium-speed CAN bus. |
| U0016 | Medium Speed CAN Communication Bus (-) low | The voltage on the negative wire of the medium-speed CAN bus is lower than expected. |
| U0017 | Medium Speed CAN Communication Bus (-) high | The voltage on the negative wire of the medium-speed CAN bus is higher than expected. |
| U0018 | Medium Speed CAN Communication Bus (-) shorted to Bus (+) | A short circuit between the positive and negative wires of the medium-speed CAN bus. |
| U0019 | Low Speed CAN Communication Bus | A general fault indicating an issue with the low-speed CAN bus. |
| U0020 | Low Speed CAN Communication Bus Performance | The low-speed CAN bus is not performing optimally. |
| U0021 | Low Speed CAN Communication Bus (+) open | An open circuit on the positive wire of the low-speed CAN bus. |
| U0022 | Low Speed CAN Communication Bus (+) low | The voltage on the positive wire of the low-speed CAN bus is lower than expected. |
| U0023 | Low Speed CAN Communication Bus (+) high | The voltage on the positive wire of the low-speed CAN bus is higher than expected. |
| U0024 | Low Speed CAN Communication Bus (-) open | An open circuit on the negative wire of the low-speed CAN bus. |
| U0025 | Low Speed CAN Communication Bus (-) low | The voltage on the negative wire of the low-speed CAN bus is lower than expected. |
| U0026 | Low Speed CAN Communication Bus (-) high | The voltage on the negative wire of the low-speed CAN bus is higher than expected. |
| U0027 | Low Speed CAN Communication Bus (-) shorted to Bus (+) | A short circuit between the positive and negative wires of the low-speed CAN bus. |
| U0028 | Vehicle Communication Bus A | A general fault indicating an issue with Vehicle Communication Bus A. |
| U0029 | Vehicle Communication Bus A Performance | Vehicle Communication Bus A is not performing optimally. |
| U0030 | Vehicle Communication Bus A (+) open | An open circuit on the positive wire of Vehicle Communication Bus A. |
| U0031 | Vehicle Communication Bus A (+) low | The voltage on the positive wire of Vehicle Communication Bus A is lower than expected. |
| U0032 | Vehicle Communication Bus A (+) high | The voltage on the positive wire of Vehicle Communication Bus A is higher than expected. |
| U0033 | Vehicle Communication Bus A (-) open | An open circuit on the negative wire of Vehicle Communication Bus A. |
| U0034 | Vehicle Communication Bus A (-) low | The voltage on the negative wire of Vehicle Communication Bus A is lower than expected. |
| U0035 | Vehicle Communication Bus A (-) high | The voltage on the negative wire of Vehicle Communication Bus A is higher than expected. |
| U0036 | Vehicle Communication Bus A (-) shorted to Bus (+) | A short circuit between the positive and negative wires of Vehicle Communication Bus A. |
| U0037 | Vehicle Communication Bus B | A general fault indicating an issue with Vehicle Communication Bus B. |
| U0038 | Vehicle Communication Bus B Performance | Vehicle Communication Bus B is not performing optimally. |
| U0039 | Vehicle Communication Bus B (+) open | An open circuit on the positive wire of Vehicle Communication Bus B. |
| U0040 | Vehicle Communication Bus B (+) low | The voltage on the positive wire of Vehicle Communication Bus B is lower than expected. |
| U0041 | Vehicle Communication Bus B (+) high | The voltage on the positive wire of Vehicle Communication Bus B is higher than expected. |
| U0042 | Vehicle Communication Bus B (-) open | An open circuit on the negative wire of Vehicle Communication Bus B. |
| U0043 | Vehicle Communication Bus B (-) low | The voltage on the negative wire of Vehicle Communication Bus B is lower than expected. |
| U0044 | Vehicle Communication Bus B (-) high | The voltage on the negative wire of Vehicle Communication Bus B is higher than expected. |
| U0045 | Vehicle Communication Bus B (-) shorted to Bus (+) | A short circuit between the positive and negative wires of Vehicle Communication Bus B. |
| U0046 | Vehicle Communication Bus C | A general fault indicating an issue with Vehicle Communication Bus C. |
| U0047 | Vehicle Communication Bus C Performance | Vehicle Communication Bus C is not performing optimally. |
| U0048 | Vehicle Communication Bus C (+) open | An open circuit on the positive wire of Vehicle Communication Bus C. |
| U0049 | Vehicle Communication Bus C (+) low | The voltage on the positive wire of Vehicle Communication Bus C is lower than expected. |
| U0050 | Vehicle Communication Bus C (+) high | The voltage on the positive wire of Vehicle Communication Bus C is higher than expected. |
| U0051 | Vehicle Communication Bus C (-) open | An open circuit on the negative wire of Vehicle Communication Bus C. |
| U0052 | Vehicle Communication Bus C (-) low | The voltage on the negative wire of Vehicle Communication Bus C is lower than expected. |
| U0053 | Vehicle Communication Bus C (-) high | The voltage on the negative wire of Vehicle Communication Bus C is higher than expected. |
| U0054 | Vehicle Communication Bus C (-) shorted to Bus (+) | A short circuit between the positive and negative wires of Vehicle Communication Bus C. |
| U0055 | Vehicle Communication Bus D | A general fault indicating an issue with Vehicle Communication Bus D. |
| U0056 | Vehicle Communication Bus D Performance | Vehicle Communication Bus D is not performing optimally. |
| U0057 | Vehicle Communication Bus D (+) open | An open circuit on the positive wire of Vehicle Communication Bus D. |
| U0058 | Vehicle Communication Bus D (+) low | The voltage on the positive wire of Vehicle Communication Bus D is lower than expected. |
| U0059 | Vehicle Communication Bus D (+) high | The voltage on the positive wire of Vehicle Communication Bus D is higher than expected. |
| U0060 | Vehicle Communication Bus D (-) open | An open circuit on the negative wire of Vehicle Communication Bus D. |
| U0061 | Vehicle Communication Bus D (-) low | The voltage on the negative wire of Vehicle Communication Bus D is lower than expected. |
| U0062 | Vehicle Communication Bus D (-) high | The voltage on the negative wire of Vehicle Communication Bus D is higher than expected. |
| U0063 | Vehicle Communication Bus D (-) shorted to Bus (+) | A short circuit between the positive and negative wires of Vehicle Communication Bus D. |
| U0064 | Vehicle Communication Bus E | A general fault indicating an issue with Vehicle Communication Bus E. |
| U0065 | Vehicle Communication Bus E Performance | Vehicle Communication Bus E is not performing optimally. |
| U0066 | Vehicle Communication Bus E (+) open | An open circuit on the positive wire of Vehicle Communication Bus E. |
| U0067 | Vehicle Communication Bus E (+) low | The voltage on the positive wire of Vehicle Communication Bus E is lower than expected. |
| U0068 | Vehicle Communication Bus E (+) high | The voltage on the positive wire of Vehicle Communication Bus E is higher than expected. |
| U0069 | Vehicle Communication Bus E (-) open | An open circuit on the negative wire of Vehicle Communication Bus E. |
| U0070 | Vehicle Communication Bus E (-) low | The voltage on the negative wire of Vehicle Communication Bus E is lower than expected. |
| U0071 | Vehicle Communication Bus E (-) high | The voltage on the negative wire of Vehicle Communication Bus E is higher than expected. |
| U0072 | Vehicle Communication Bus E (-) shorted to Bus (+) | A short circuit between the positive and negative wires of Vehicle Communication Bus E. |
| U0073 | Control Module Communications Bus Off | A critical fault indicating that one or more control modules on the communications bus have stopped communicating. |
| U0100 | Lost Communication with ECM/PCM A | Indicates that communication has been lost with the Engine Control Module (ECM) or Powertrain Control Module (PCM), which are responsible for managing the engine and transmission. |
| U0101 | Lost Communication with TCM | Communication has been lost with the Transmission Control Module (TCM). |
| U0102 | Lost Communication with Transfer Case Control Module | Communication has been lost with the Transfer Case Control Module, which controls the operation of the transfer case in four-wheel-drive vehicles. |
| U0103 | Lost Communication with Gear Shift Module | Indicates that communication has been lost with the gear shift module, which is responsible for relaying gear shift information to other systems. |
| U0104 | Lost Communication with Cruise Control Module | Communication has been lost with the cruise control module. |
| U0105 | Lost Communication with Fuel Injector Control Module | Communication has been lost with the Fuel Injector Control Module. |
| U0192 | Lost Communication with Television | Communication has been lost with the television module, likely related to the infotainment system. |
| U0197 | Lost Communication with Telephone Control Module | Communication has been lost with the telephone control module, typically part of the vehicle’s communication and infotainment system. |
| U0198 | Lost Communication with Telematic Control Module | Communication has been lost with the telematic control module, |
