The P2064: Reductant/Regeneration Supply Control Circuit High refers to a fault where the control circuit for the reductant (DEF) or regeneration system is experiencing higher-than-expected voltage. This can prevent the system from properly controlling the supply of reductant or regeneration fluid, leading to malfunctioning emissions control. The issue may be caused by high voltage, faulty components, wiring problems, or connector issues.
P2064 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P2064: Reductant/Regeneration Supply Control Circuit High |
| Is it serious? | Yes, it can affect the functionality of the reductant or regeneration system, leading to increased emissions. |
| Possible causes | – High voltage in the supply control circuit – Faulty components or wiring – Connector issues |
| How to diagnose? | – Measure voltage in the supply control circuit – Test the components – Check wiring and connectors |
P2064 Meaning
The P2064 code indicates that the supply control circuit, which manages the delivery of reductant (DEF) or regeneration fluid into the exhaust system, is experiencing high voltage. This excessive voltage could result in improper operation of the system, leading to poor emissions control. The issue could be related to a fault in the wiring, connectors, or components such as the reductant injector or pump, causing a malfunction in the reductant system.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for additional fault codes related to the reductant or regeneration system that may provide further information. | OBD-II Scanner |
| Measure Voltage in the Circuit | Use a multimeter to measure the voltage in the supply control circuit and compare it to the manufacturer’s specifications to confirm high voltage. | Multimeter |
| Test Components | Test the components involved, such as the reductant injector or pump, using diagnostic tools to ensure they are functioning within the correct range. | Multimeter, Diagnostic Tool |
| Inspect Wiring and Connectors | Check the wiring and connectors for any signs of damage, corrosion, or loose connections that could result in high voltage in the circuit. | Flashlight, Multimeter |
| Clear the Code and Test Drive | After repairs, clear the fault code with an OBD-II scanner and take the vehicle for a test drive to confirm the issue has been resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
| Recheck for Codes | Re-scan the vehicle after the test drive to ensure the P2064 code does not return. If it reappears, further diagnostics may be required. | OBD-II Scanner |
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