P2063 Fault Code

Reductant Supply Control Circuit Low

• What does that mean?
• Symptoms
• Causes
• Solutions

The P2063 fault code indicates an issue with the reductant supply control circuit, specifically that the circuit voltage is lower than the expected range. This often pertains to the diesel exhaust fluid (DEF) system used in vehicles with selective catalytic reduction (SCR) technology to reduce emissions.

What are the symptoms of the P2063 code?

Symptoms associated with the P2063 fault code may include:

• Check Engine Light (CEL) illuminating on the dashboard.
• Reduced engine power or performance due to emissions control limitations.
• Possible messages or warnings related to DEF levels or system performance.
• Increased emissions output as the system fails to operate correctly.

What causes the P2063 code?

Common causes of the P2063 fault code include:

• Damaged or corroded wiring in the reductant supply control circuit.
• A faulty reductant pump that is not delivering fluid as needed.
• Issues with the DEF tank or sensors associated with monitoring the reductant levels.
• A blown fuse that impacts the operation of the reductant system.

How to fix P2063?

To resolve the P2063 fault code, one should:

• Inspect the wiring and connectors of the reductant supply control circuit for damage or corrosion, repairing or replacing as necessary.
• Test the reductant pump for proper operation and replace it if it is found to be faulty.
• Check the DEF tank and associated sensors to ensure they are functioning properly.
• Replace any blown fuses related to the reductant system and clear the fault codes after repairs are made.