The P20BD: Reductant Heater ‘B’ Control Circuit/Open refers to an issue where the control circuit for reductant heater ‘B’ is open, meaning there is a break or disconnection in the circuit. This may result in the heater failing to operate, which could affect the reductant system’s performance.
P20BD – Quick Overview
| Code | Information |
|---|---|
| Meaning | P20BD: Reductant Heater ‘B’ Control Circuit/Open |
| Is it serious? | Yes, as this can lead to the reductant system not working correctly, potentially increasing vehicle emissions. |
| Possible causes | – Open circuit in the reductant heater ‘B’ control circuit – Faulty reductant heater ‘B’ – Faulty control module |
| How to diagnose? | – Inspect the wiring for open circuits – Test reductant heater ‘B’ – Check the control module functionality |
P20BD Meaning
The P20BD fault code indicates that the control circuit for reductant heater ‘B’ has an open circuit, which means there is a break or disconnection preventing the heater from functioning properly. This can affect the vehicle’s emissions control system and overall performance. The issue may arise from faulty wiring, a malfunctioning heater, or a problem with the control module.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to look for additional codes that might help identify the source of the issue. | OBD-II Scanner |
| Inspect Wiring for Open Circuits | Inspect the wiring and connections leading to reductant heater ‘B’ for open circuits, breaks, or loose connections. | Flashlight, Multimeter |
| Test Reductant Heater ‘B’ | Use a diagnostic tool to test reductant heater ‘B’ and ensure it is functioning within specifications. | Multimeter, Diagnostic Tool |
| Check the Control Module | Test the control module to confirm it is functioning correctly and not causing the open circuit issue. | Diagnostic Tool |
| Repair or Replace Wiring/Heater | If an open circuit is found, repair the wiring or replace reductant heater ‘B’ as needed. | Wiring Kit, Replacement Heater |
| Clear the Code and Test Drive | After making repairs, clear the code using an OBD-II scanner and test drive the vehicle to ensure the issue is resolved. | OBD-II Scanner, Vehicle Manual |
| Recheck for Codes | After the test drive, rescan the vehicle to ensure the P20BD code does not return. | OBD-II Scanner |
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