This page contains links to third parties, if you click through those links we may receive a commission at no extra cost to you.

Engine Fault Code P2064

Reductant Supply Control Circuit High

Care Engine Code Reader
The engine fault code P2064 refers to a problem in the reductant supply control circuit, specifically indicating that the circuit is reading a high voltage. This code is often related to the vehicle`s emissions system, particularly in diesel engines that use a selective catalytic reduction (SCR) system. The SCR system helps reduce harmful emissions by injecting a urea-based solution (often called diesel exhaust fluid or DEF) into the exhaust stream.

While P2064 generally has the same meaning across various manufacturers, the specific implications can vary slightly depending on the vehicle make and model. Here are some alternative meanings based on different brands:

1. Audi: May indicate an issue with the DEF pump or the wiring in the reductant supply circuit.
2. Volkswagen: Similar to Audi, it could suggest a fault in the DEF system or a problem with the sensors monitoring the reductant level.
3. Mercedes-Benz: Often points to a malfunction in the SCR system, possibly related to the DEF dosing module.
4. Porsche: Could indicate a problem with the emissions control system, particularly in models equipped with diesel engines.
5. Jaguar: May refer to issues with the SCR system, including the DEF injector or related components.
6. Land Rover: Similar to Jaguar, it can indicate a fault in the DEF system or wiring issues leading to incorrect readings.

If you encounter this code, it`s essential to check the wiring and connectors related to the reductant supply circuit. You might also want to inspect the DEF pump and injector for proper operation. Always consult the specific service manual for your vehicle for more detailed diagnostics and repair procedures.
The Engine Fault Code P2064 indicates a problem with the reductant supply control circuit, which is often related to the diesel exhaust fluid (DEF) system in diesel vehicles. This code usually means that there`s a high voltage signal in the circuit that controls the flow of DEF, which is used to reduce harmful emissions.

Here are some common causes for this fault code, and they can vary by manufacturer:

1. Faulty Reductant Control Module: This module controls the amount of DEF injected. If it fails, it can send incorrect signals, leading to a high circuit reading.

2. Wiring Issues: Damaged or corroded wiring in the reductant supply circuit can cause high resistance or short circuits, triggering the code.

3. Faulty DEF Pump: If the DEF pump is malfunctioning, it may not supply the correct amount of fluid, which can also affect the circuit readings.

4. Sensor Issues: The system relies on various sensors to monitor DEF levels and flow. A faulty sensor can give incorrect readings, causing the code to trigger.

5. DEF Quality Issues: If the DEF is contaminated or not of the correct quality, it can affect the system`s performance and lead to fault codes.

6. ECU Problems: The engine control unit (ECU) itself may have issues or software glitches that misinterpret the signals from the reductant supply circuit.

Manufacturer-Specific Considerations:

– Volkswagen/Audi: These brands may have additional issues related to the AdBlue system, which is their version of DEF. Look for specific software updates or recalls that may apply.

Mercedes-Benz: Mercedes vehicles might have specific DEF tank issues or unique wiring layouts that could cause this code.

– Jaguar and Land Rover: These brands often use similar DEF systems as others, but their wiring harnesses and module configurations may differ, leading to unique troubleshooting steps.

Porsche: While less common, if a Porsche diesel model has this issue, it could relate to the same factors as other brands but may involve more complex software interactions.

Mini: If a Mini diesel model throws this code, it could be related to the BMW engineering behind it, so checking for BMW-specific issues might be necessary.

When diagnosing this code, it`s essential to inspect the wiring, connectors, and components related to the DEF system. Using a diagnostic scanner can help pinpoint the exact issue. If you`re not comfortable with repairs, it might be best to consult a professional mechanic.
The Engine Fault Code P2064 refers to a problem with the reductant supply control circuit, which is often related to the diesel exhaust fluid (DEF) system. This code usually shows up in vehicles with diesel engines that use DEF to reduce emissions. Heres how to address this issue, with some manufacturer-specific notes:

General Steps to Fix P2064:

1. Check the DEF Level:
– Ensure that the diesel exhaust fluid tank is filled to the proper level. A low DEF level can trigger this code.

2. Inspect the Wiring and Connectors:
– Look for damaged or corroded wiring and connectors in the reductant supply circuit. Repair or replace any damaged components.

3. Test the Reductant Pump:
– The reductant pump is responsible for supplying DEF to the system. Use a multimeter to check if the pump is receiving power. If not, trace the wiring back to find any issues.

4. Check the Reductant Injector:
– Inspect the injector for clogs or damage. Clean or replace it if necessary.

5. Scan for Additional Codes:
– Use an OBD-II scanner to check for any other codes that might help identify the problem.

6. Reset the Code:
– After making repairs, clear the code using an OBD-II scanner and take the vehicle for a test drive to see if the code returns.

Manufacturer-Specific Notes:

– Volkswagen/Audi:
– These vehicles may have additional components like a DEF heater. Make sure to check if its functioning properly.

Mercedes-Benz:
– The DEF system on Mercedes models can be sensitive. Check for software updates that might address known issues.

– Jaguar/Land Rover:
– These vehicles may have more complex systems. If the problem persists, consider consulting a dealer or a specialized mechanic.

Porsche:
– For Porsche models, ensure that the DEF used meets manufacturer specifications, as using the wrong fluid can cause issues.

Mini:
– Mini vehicles with diesel engines may have unique wiring or connector issues. Inspect thoroughly.


Fixing the P2064 code involves checking the DEF level, inspecting wiring, and testing the pump and injector. Always refer to the vehicles service manual for specific procedures and specifications. If youre not comfortable performing these checks, its best to consult a professional mechanic.
The P2064 code indicates a problem with the reductant supply control circuit, which is often related to the diesel exhaust fluid (DEF) system in vehicles that use it. This code is common in diesel engines, especially in European cars like Audi, Mercedes, and Jaguar.

General Safety Considerations:
1. Immediate Safety: Driving with this code may not pose an immediate safety risk, but it can lead to reduced engine performance and efficiency. You`ll likely notice issues like decreased power or increased emissions.

2. Long-Term Effects: If you continue to drive the vehicle without addressing the issue, you could face more significant problems, including potential damage to the engine or emissions system.

3. Check Engine Light: The presence of this code usually means the check engine light is on. Ignoring it could lead to more severe issues down the line.

Manufacturer-Specific Considerations:

1. Audi:
– Driving with this code may lead to a reduced power mode (limp mode). It`s advisable to get it checked soon.

2. Mercedes:
– Similar to Audi, you may experience reduced power. Its best to address the issue promptly to avoid further complications.

3. Porsche:
– Depending on the model, you might not see immediate effects, but it`s crucial to fix it to maintain performance and emissions compliance.

4. Mini:
– Mini vehicles may have a similar response as other European brands. Driving may be possible, but it`s not recommended without repairs.

5. Jaguar:
– Jaguars may enter limp mode, affecting drivability. It`s best to have the issue diagnosed and repaired.

6. Land Rover:
– Land Rovers can experience significant power loss, and driving with this code isn`t advisable. Repairs should be prioritized.


While it might be safe to drive for a short period with the P2064 code, it`s not recommended. Each manufacturer may have different responses to the issue, but the general advice is to have it checked out as soon as possible to prevent further damage. If you`re unsure, it`s always best to consult a professional mechanic.

OBD Codes Explained

Engine Codes

P is for PowerTrain - Engine and Transmission.

P0 Indicates Generic Powertrain Codes

P0 Codes indicate problems with the powertrain and are common for all vehicles using the OBD-II Standard.

P1 Enhanced Manufacturer Specific Codes

P1 Codes are specific to manufacturers.

Sub-System

The 3rd Digit indicates the Sub-System

1 – Emission Management

2 – Injector Circuit

3 – Ignition

4 – Emission Control

5 – Vehicle Speed and Idle

6 – Computer and Output

7 – Transmission

8 – Transmission

9 – Reserved

0 – Reserved

0
    0
    Your Cart
    Your cart is emptyReturn to Shop

    Need parts advice?

    Tell us what you need and we will be in touch shortly.

    Contact Information
    Vehicle Information