Is your Volkswagen’s check engine light illuminated? It can be unsettling to see that warning light appear on your dashboard. Fortunately, modern vehicles like your Volkswagen are equipped with an On-Board Diagnostic (OBD) system. When this system detects an issue, it generates a trouble code. These codes are designed to help technicians quickly and accurately pinpoint problems. If you have access to an OBD-II scanner, understanding these codes can give you a valuable head start in diagnosing what might be amiss with your VW. Dive into our comprehensive Vw Obd2 Codes List to get a better understanding of potential issues.
Decoding Your Volkswagen OBD2 Codes
The OBD-II system is a standardized system used across the automotive industry, including Volkswagen. Its primary function is to monitor the performance of your vehicle’s engine, emissions system, and other critical components. When the system detects a malfunction outside of normal parameters, it triggers the check engine light and stores a corresponding Diagnostic Trouble Code (DTC). These codes are invaluable for mechanics and even for informed car owners to understand the nature of the problem.
Using an OBD-II scanner, you can retrieve these codes from your Volkswagen’s computer. These scanners are readily available and range from basic handheld devices to more advanced professional tools. Once you have the code, you can consult resources like the list below to get an initial idea of what might be causing the issue.
Here’s a breakdown of common VW OBD2 codes and potential problems they indicate:
| Code | Common Problems That Trigger This Code |
|---|---|
| P0010 | Variable Valve Timing (VVT) Actuator Circuit/Open (Bank 1): This code often suggests issues within the variable valve timing system. Potential culprits include a faulty Powertrain Control Module (PCM), a failing VVT actuator itself, or wiring problems within the actuator circuit. This system is crucial for engine efficiency and performance. |
| P0011 | “A” Camshaft Position – Timing Over-Advanced or System Performance (Bank 1): This code, along with P0012, points to timing issues within the camshaft. Possible causes range from a malfunctioning camshaft variable timing solenoid or a worn timing chain to something as simple as low engine oil level or using the wrong type of oil. Incorrect engine timing can significantly impact engine performance and fuel economy. |
| P0012 | “A” Camshaft Position – Timing Over-Retarded (Bank 1): Similar to P0011, this code indicates camshaft timing problems, but in the opposite direction. Again, check the camshaft variable timing solenoid, engine oil level and type, timing chain wear, and overall engine timing. |
| P0013 | Variable Valve Timing (VVT) Actuator Circuit/Open (Bank 2): Mirrors P0010, but refers to Bank 2 of the engine. The issues are the same: PCM failure, VVT actuator problems, or wiring faults. |
| P0014 | “B” Camshaft Position – Timing Over-Advanced or System Performance (Bank 1): Similar to P0011 but potentially related to a different camshaft or sensor depending on the VW engine configuration. Investigate the same potential causes as P0011 and P0012. |
| P0101 | Mass Air Flow (MAF) Circuit Range/Performance: The Mass Air Flow sensor measures the amount of air entering the engine, crucial for fuel mixture calculations. This code can be triggered by a variety of air intake issues, including large vacuum leaks from split intake boots or PCV hoses, defective intake manifold gaskets, or a failing MAF sensor itself. Wiring problems to the MAF sensor and even outdated PCM software can also be responsible. |
| P0102 | Mass Air Flow (MAF) Circuit Low Input: This indicates a low signal from the MAF sensor. Check for a disconnected or damaged MAF sensor, wiring issues within the MAF sensor circuit (loose or corroded terminals), or a faulty MAF sensor. A clean and properly functioning MAF sensor is vital for correct engine operation. |
| P0113 | Intake Air Temperature Circuit High Input: This code points to a high reading from the Intake Air Temperature (IAT) sensor. A defective IAT sensor is a primary suspect, but also consider a dirty air filter restricting airflow, a failing MAF sensor (which often integrates the IAT sensor), or wiring/connection problems. |
| P0128 | Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature): This code signals that the engine coolant is not reaching the expected operating temperature within a reasonable time. A defective engine thermostat (often stuck open) is the most common cause. However, also inspect the Engine Coolant Temperature Sensor, Intake Air Temperature Sensor, cooling system for leaks, low coolant levels, dirty coolant, and even a constantly running engine cooling fan. |
| P0135 | O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1): This code indicates a problem with the heater circuit of the oxygen sensor (O2 sensor) or Air Fuel Ratio sensor. Besides a defective sensor itself or its heater circuit, consider exhaust or intake air system leaks, low fuel pressure, a faulty Engine Coolant Temperature Sensor, wiring issues, outdated PCM software, or even a defective PCM. The O2 sensor is critical for monitoring exhaust gases and adjusting fuel mixture. |
| P0171 | System Too Lean (Bank 1): A lean condition means there’s too much air and not enough fuel in the air-fuel mixture. This code can be caused by vacuum leaks (intake manifold gaskets, hoses), a faulty MAF sensor, a plugged fuel filter or weak fuel pump restricting fuel delivery, or clogged or dirty fuel injectors. Software updates for the control module can sometimes resolve this issue. |
| P0174 | System Too Lean (Bank 2): Similar to P0171, but refers to Bank 2. Investigate the same potential causes: vacuum leaks, MAF sensor issues, fuel delivery problems, and potentially outdated PCM software. |
| P0200 – P0205 | Injector Circuit Malfunction (Cylinder Specific): These codes (P0201, P0202, P0203, P0205) and the general P0200 code point to issues with fuel injectors. This could be a defective injector, wiring or connector problems, a plugged or dirty injector, or even dirt in the fuel injector itself. P0202 specifically can also indicate a malfunction in the PCM’s fuel injector driver circuit. |
| P0300 – P0304 | Random/Multiple Cylinder Misfire Detected (and Cylinder Specific Misfire): These are misfire codes. P0300 is a random misfire, while P0301, P0302, P0303, and P0304 indicate misfires in specific cylinders. Misfires can stem from a wide range of issues, from worn spark plugs, ignition wires, coils, and distributor components to incorrect ignition timing, vacuum leaks, low fuel pressure, EGR system problems, a faulty MAF sensor, crankshaft/camshaft sensors, throttle position sensor, or even mechanical engine problems like low compression or leaking head gaskets. |
| P0401 | Exhaust Gas Recirculation Flow Insufficient Detected: This code indicates insufficient flow in the Exhaust Gas Recirculation (EGR) system, which reduces NOx emissions. Common causes include carbon buildup restricting EGR passages, a defective EGR valve, vacuum or electrical signal problems to the EGR valve, a malfunctioning EGR vacuum supply solenoid, or issues with feedback sensors like the MAP sensor, DPFE sensor, EVP sensor, or EGR temperature sensor. |
| P0420 & P0430 | Catalyst System Efficiency Below Threshold (Bank 1 & Bank 2): These codes signal problems with the catalytic converter’s efficiency. P0420 refers to Bank 1, and P0430 to Bank 2. An inefficient catalytic converter is the primary suspect. However, also consider defective front or rear oxygen sensors, engine misfires, and in the case of P0430, internal engine damage leading to oil consumption which can damage the catalytic converter. |
| P0440, P0441, P0442, P0455 | Evaporative Emission Control System Malfunction (Various): These codes relate to the Evaporative Emission Control System (EVAP), which prevents fuel vapors from escaping into the atmosphere. Common issues include a missing or defective fuel cap, damage to the fuel tank filler neck, torn or punctured EVAP hoses, a defective fuel tank sending unit gasket or seal, a split or damaged carbon canister, defective EVAP vent or purge valves, a damaged fuel tank, and related sensors and pumps. |
| P0500 & P0501 | Vehicle Speed Sensor (VSS) Malfunction: These codes indicate problems with the Vehicle Speed Sensor, which provides speed information to the car’s computer. A defective VSS or speedometer, wiring or connector issues, CAN bus communication problems, or a defective transmission/differential VSS drive gear can trigger these codes. |
| P0505, P0506, P0507 | Idle Air Control (IAC) System Malfunction: These codes relate to the Idle Air Control system, which regulates engine idle speed. Common causes include a defective or sticking IAC motor, intake manifold vacuum leaks, carbon buildup in the throttle body air passages, and in the case of P0506 and P0507, a defective power steering pressure switch. P0507 can also be triggered by a defective coolant temperature sensor or charging system/alternator issues. |
| P0600 – P0605 | PCM/ECM Internal Control Module Malfunction: These codes indicate various internal problems with the Powertrain Control Module (PCM) or Engine Control Module (ECM), the car’s main computer. These can range from PCM failure, wiring/connection issues, ground circuit problems, voltage problems, memory module failures, and CAN bus communication issues. These codes often require professional diagnosis and PCM replacement or reprogramming. |
| P0700, P0705, P0706, P0720, P0730 | Transmission Control System Malfunction: These codes point to various transmission-related issues. P0700 is a general transmission control system malfunction. Others like P0705 and P0706 relate to the Transmission Range Sensor (PRNDL input). P0720 is for Output Speed Sensor issues. P0730 indicates incorrect gear ratio. Common causes across these codes include defective shift solenoids, a faulty Engine Coolant Temperature Sensor, a defective valve body, dirty transmission fluid, and wiring/connector problems. |
| P0841, P0842, P0845, P0846, P0847 | Transmission Fluid Pressure Sensor/Switch Circuit Range/Performance: These codes indicate issues with the transmission fluid pressure sensor circuit. Possible causes include Transmission Control Module (TCM) failure, low transmission fluid level, a faulty transmission fluid pressure sensor, and wiring problems. |
| P0901, P0935, P0942, P0944, P0961 | Clutch/Hydraulic/Shift Solenoid Circuit Malfunction: These codes cover various clutch and hydraulic system malfunctions, often related to automatic transmissions or automated manual transmissions. Causes can range from clutch master cylinder or solenoid failure, hydraulic power unit assembly failure, TCM failure, clogged transmission filter, low fluid level, transmission oil pump failure, and specific shift solenoid failures. |
| P0A08, P0A0D, P0A0F, P0A7F, P0A80, P0B22, P0B24, P0B26, P0B28, P0B30, P0C00, P0C09, P0C11, P0C14, P0C15 | Hybrid/Electric Vehicle System Malfunction: These codes are specific to hybrid and electric Volkswagen models, indicating a wide array of potential issues within the high-voltage systems, inverters, converters, battery systems, drive motor generators, and related control modules. Diagnosis and repair of these codes require specialized knowledge and equipment. |
| P2000, P2002 | NOx Trap Performance Below Threshold (Bank 1): These codes relate to the Diesel Particulate Filter (DPF) and NOx reduction systems in diesel Volkswagens. They can be triggered by a DPF failure, intake air leaks, or a dirty/uncalibrated Mass Airflow (MAF) sensor. |
| P2004, P2006 | Intake Manifold Runner Control Stuck Open/Closed: These codes indicate problems with the Intake Manifold Runner Control (IMRC) system, which optimizes airflow into the engine. A failed IMRC actuator, problems with the intake manifold or linkage, wiring issues, or restricted vacuum lines can be responsible. |
| P2101, P2122, P2135, P2138 | Throttle/Accelerator Pedal Position Sensor/Switch Circuit Range/Performance: These codes relate to the throttle and accelerator pedal position sensors, which control engine power output. Possible causes include a faulty Accelerator Pedal Position (APP) assembly, PCM failure, throttle control motor failure, Throttle Position Sensor (TPS) failure, and wiring problems. |
| P2181 | Cooling System Performance: This code indicates general cooling system performance issues. Check for an engine coolant heater failure, low coolant level, or a thermostat failure. |
| P2210, P2213, P2237, P2238, P2251 | NOx Sensor Circuit Malfunction: These codes signal problems with the NOx sensor, which monitors nitrogen oxides in the exhaust. Causes include a faulty NOx sensor, PCM failure, wiring issues, and exhaust leaks. |
| P2302, P2303, P2305, P2308, P2310 | Ignition Coil “A” Primary/Secondary Circuit Malfunction: These codes indicate problems with specific ignition coils. Causes include ignition coil failure, PCM failure, and wiring issues. |
| P2401, P2402, P2422 | Evap Leak Detection Pump/Vent Valve Control Circuit Malfunction: These codes relate to specific components within the EVAP system: the leak detection pump and vent valve. Causes include failures of these components, PCM failure, and wiring issues. |
| P2431, P2432 | Secondary Air Injection System Air Flow/Pressure Sensor Circuit Range/Performance: These codes indicate issues with the Secondary Air Injection System, which helps reduce emissions during cold starts. Causes include air control solenoid failure, PCM failure, secondary air system pressure sensor failure, and wiring issues. |
| P2500, P2501, P2503, P2509, P250C | Charging System/Oil Level Sensor Circuit Malfunction: These codes relate to the charging system and oil level sensor. Causes include alternator failure, battery failure, PCM failure, wiring issues, and oil level sensor failure. |
| P2601, P2607, P2609 | Coolant Heat Storage/Intake Air Heater Control Circuit Malfunction: These codes relate to coolant heat storage and intake air heater systems, often found in diesel vehicles. Causes include water pump failure, relay issues, PCM failure, wiring issues, and intake air heater problems. |
| P2610 | PCM Internal Engine Off Timer Performance: This code suggests an internal problem within the PCM itself or issues with its power or ground circuits. |
| P2614 | Camshaft Position Sensor Circuit Low Voltage: This code points to a low voltage signal from the Camshaft Position Sensor. Causes include a broken tone ring, CMP sensor failure, PCM failure, and wiring problems. |
| P2706, P2711, P2714, P2716, P2723, P2803, P2806, P2809, P2810, P2815 | Transmission Shift Solenoid/Range Sensor/Pressure Control Solenoid Circuit Malfunction: These codes cover a range of transmission solenoid and sensor issues. Common causes include TCM failure, low transmission fluid level, transmission shift solenoid failure, transmission range sensor failure, transmission pressure control solenoid failure, and wiring problems. |
| P2A00, P2A01, P2A03, P2A04 | O2 Sensor Circuit Range/Performance (Universal): These codes relate to universal oxygen sensor circuit performance. Causes include exhaust leaks, oxygen sensor failure, PCM failure, and wiring issues. |
| P2BA8 | NOx Exceedance – Insufficient Reagent Quality: This code specifically relates to diesel vehicles and NOx sensor/DPF issues. Causes include faulty NOx sensors, wiring problems, poor electrical connections, and a faulty Diesel Particulate Filter (DPF). |
| P3000, P3100, P3400, P3401 | Hybrid/Cylinder Deactivation System Malfunction: These codes relate to hybrid system failures, low fuel level in hybrid systems, cylinder deactivation system faults, and related issues like low engine oil or variable valve timing problems. |
| B0081 | Driver Frontal Stage 1 Airbag Deployment Control: This is a body code related to the airbag system. Causes include wiring issues, control module problems, and airbag malfunctions. |
| C0040 | Right Front Wheel Speed Sensor Circuit Malfunction: This is a chassis code related to the ABS system. Causes include a faulty wheel speed sensor, circuit problems, reluctor issues, and ABS module problems. |
| U0001, U0073, U0100, U0107, U0121 | Communication Bus Malfunction: These are network communication codes indicating problems with the vehicle’s communication network (CAN bus). Causes include faulty control modules (PCM, ABS, TAC), circuit problems, and CAN bus issues. U0107 and U0121 can also be triggered by a dead battery. |
Understanding your Volkswagen check engine light and associated OBD2 codes is the first step in diagnosing potential vehicle issues.
When to Consult a Volkswagen Specialist
While this VW OBD2 codes list provides a helpful starting point, it’s important to remember that diagnosing modern vehicles can be complex. The potential causes listed are common possibilities, but the exact root cause of a specific code in your Volkswagen might require further expert investigation.
Codes beginning with “P1” are often Volkswagen-specific OBD2 codes and are not included in this general list. These manufacturer-specific codes often delve into more intricate system details and require specialized Volkswagen diagnostic tools and knowledge to interpret accurately.
For accurate diagnosis and repair, especially when dealing with check engine lights and OBD2 codes, consulting certified Volkswagen technicians is highly recommended. They possess the expertise, experience, and access to advanced Volkswagen diagnostic equipment to ensure your vehicle is repaired correctly and to Volkswagen’s stringent standards.
Don’t let a check engine light cause unnecessary worry. Understanding your VW OBD2 codes list is empowering, but professional help is often the most effective way to resolve vehicle issues efficiently and reliably.
For further assistance with your Volkswagen OBD-II trouble codes, or to schedule a professional diagnosis, contact us today at 877-421-1793 to speak with our knowledgeable service team or conveniently schedule a service appointment online.
