The P20EB: Reductant Control Module Power Relay De-Energized Performance – Too Late fault code indicates that the power relay in the reductant control module is de-energizing later than intended, which may disrupt the reductant injection system’s performance and emissions control. The issue could be caused by a faulty power relay or a malfunction in the reductant control module.
P20EB – Quick Overview
| Code | Information |
|---|---|
| Meaning | P20EB: Reductant Control Module Power Relay De-Energized Performance – Too Late |
| Is it serious? | Yes, improper relay timing can cause reductant system malfunctions, affecting emissions control. |
| Possible causes | – Power relay de-energized too late – Faulty relay – Issues with the reductant control module |
| How to diagnose? | – Check the timing of the power relay de-energization – Test the power relay – Inspect the reductant control module |
P20EB Meaning
The P20EB fault code indicates that the power relay in the reductant control module is de-energizing later than it should, which can impact the timing and function of the reductant injection system. This could lead to improper operation of the system and potential emissions control problems. The issue might be caused by a malfunctioning relay or control module.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for other codes related to the reductant system or power relay, which may provide more details about the issue. | OBD-II Scanner |
| Check the Timing of Power Relay De-Energization | Use a diagnostic tool to monitor the timing of the power relay de-energization and ensure it aligns with the manufacturer’s specifications. | Diagnostic Tool |
| Test the Power Relay | Use a multimeter to test the power relay’s functionality and verify that it de-energizes at the correct time. | Multimeter, Diagnostic Tool |
| Inspect the Reductant Control Module | Inspect the reductant control module for errors or faults in controlling the power relay, ensuring proper system function. | Diagnostic Tool |
| Repair or Replace Faulty Components | If the power relay or control module is found to be faulty, repair or replace the necessary components to ensure correct operation. | Replacement Parts, Tools |
| Clear the Code and Test Drive | After completing repairs, clear the fault code using an OBD-II scanner and take the vehicle for a test drive to confirm the issue is resolved. | OBD-II Scanner, Vehicle Manual |
| Recheck for Codes | After the test drive, rescan the vehicle to ensure the P20EB code does not reappear. | OBD-II Scanner |
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