The P20C6: Reductant Heater ‘D’ Control Circuit Performance refers to an issue where reductant heater ‘D’ is not performing as expected. This may be due to faults in the heater itself or issues with the control module responsible for its operation.
P20C6 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P20C6: Reductant Heater ‘D’ Control Circuit Performance |
| Is it serious? | Yes, this can lead to improper functioning of the reductant system, potentially causing emission control issues. |
| Possible causes | – Heater ‘D’ performance issues – Faulty heater – Faulty control module |
| How to diagnose? | – Test the performance of reductant heater ‘D’ – Inspect for faults in the heater – Check the control module functionality |
P20C6 Meaning
The P20C6 fault code indicates a performance issue in the control circuit for reductant heater ‘D’. This could mean the heater is underperforming or malfunctioning, which can disrupt the vehicle’s emission reduction system. Possible causes include a defective heater, wiring issues, or problems with the control module managing the heater.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for any additional codes that could provide more insight into the issue. | OBD-II Scanner |
| Test Reductant Heater ‘D’ Performance | Use a diagnostic tool to test the performance of reductant heater ‘D’ and verify if it meets manufacturer specifications. | Multimeter, Diagnostic Tool |
| Inspect the Heater for Faults | Visually inspect heater ‘D’ for any signs of damage, wear, or other issues that could affect its performance. | Flashlight, Multimeter |
| Check the Control Module | Verify that the control module is functioning correctly and sending proper signals to heater ‘D’. | Diagnostic Tool |
| Repair or Replace Heater | If performance issues are detected, repair or replace the heater to restore proper function. | Replacement Heater, Tools |
| Clear the Code and Test Drive | After repairs, clear the code using an OBD-II scanner and test drive the vehicle to verify the problem is resolved. | OBD-II Scanner, Vehicle Manual |
| Recheck for Codes | After the test drive, rescan the vehicle to ensure the P20C6 code does not return. | OBD-II Scanner |
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