Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the light that tells you something is wrong with the system that reduces pollution from your car.
The P065D code indicates an issue with the control circuit for the lamp that signals a malfunction in the reductant system, which is part of the emission control system.
The P065D code is set when the Engine Control Module (ECM) detects a malfunction in the control circuit for the reductant system malfunction indicator lamp. This lamp is used to alert the driver to issues within the reductant system, which is responsible for reducing harmful emissions by using a reductant fluid, typically Diesel Exhaust Fluid (DEF).
• Malfunction indicator lamp not illuminating
• Check engine light may be on
• Emission-related warning messages on the dashboard
• Faulty reductant system malfunction lamp
• Open or shorted wiring in the lamp control circuit
• Faulty ECM
Reductant: A substance used to reduce emissions, often Diesel Exhaust Fluid (DEF).
ECM: Engine Control Module, the computer that controls engine functions.
• Check the wiring and connectors for the lamp control circuit.
• Test the reductant system malfunction lamp for proper operation.
• Use a scan tool to check for additional trouble codes.
• Repair or replace damaged wiring or connectors.
• Replace the reductant system malfunction lamp if faulty.
• Reprogram or replace the ECM if necessary.
• OBD-II scan tool
• Multimeter
• Wiring diagram for the vehicle
$100 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly check and maintain the reductant system.
• Inspect wiring and connectors for damage.
• Ensure the ECM is up to date with the latest software.
Sensor Issue
• Have the vehicle inspected by a professional if the check engine light is on.
• Avoid ignoring emission-related warnings as they can lead to more serious problems.
• Regular maintenance can prevent issues with the reductant system.
Check with the vehicle manufacturer for warranty coverage on emission-related components.
The P065D code has been associated with issues in vehicles equipped with diesel engines and reductant systems since the introduction of stricter emission standards.
Moderate – While the vehicle may still operate, emissions may be higher than acceptable levels.
Operating a vehicle with a malfunctioning emission control system may violate environmental regulations.
• Vehicle at operating temperature
• Engine running
The reductant system malfunction lamp is typically located on the vehicle's dashboard.
Q: What is a reductant system?
A: A reductant system is used in diesel vehicles to reduce harmful emissions by injecting a fluid into the exhaust stream.
Q: Can I drive with a P065D code?
A: While you can drive, it's advisable to address the issue to ensure your vehicle meets emission standards.
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