The P20C1: Reductant Heater ‘C’ Control Circuit/Open refers to a condition where the control circuit for reductant heater ‘C’ has an open circuit. This means there is a disconnection or break in the circuit, preventing the heater from operating correctly. The issue could be caused by faulty wiring, a defective heater, or a malfunctioning control module.
P20C1 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P20C1: Reductant Heater ‘C’ Control Circuit/Open |
| Is it serious? | Yes, this can cause the reductant system to malfunction, leading to ineffective emissions control. |
| Possible causes | – Open circuit in the reductant heater ‘C’ control circuit – Faulty reductant heater ‘C’ – Faulty control module |
| How to diagnose? | – Inspect the wiring for open circuits – Test reductant heater ‘C’ – Check the control module functionality |
P20C1 Meaning
The P20C1 fault code indicates that the control circuit for reductant heater ‘C’ has an open circuit, meaning the circuit is broken or disconnected. This can lead to the heater not working, which affects the vehicle’s emissions reduction system. The cause could be damaged wiring, a faulty heater, or a control module issue.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to see if there are any other related codes that could help pinpoint the issue. | OBD-II Scanner |
| Inspect Wiring for Open Circuits | Visually inspect the wiring for any breaks, disconnections, or damage in the control circuit for reductant heater ‘C’. | Flashlight, Multimeter |
| Test Reductant Heater ‘C’ | Use a diagnostic tool to check the performance and functionality of reductant heater ‘C’. | Multimeter, Diagnostic Tool |
| Check the Control Module | Verify that the control module is working correctly and not contributing to the open circuit issue. | Diagnostic Tool |
| Repair or Replace Wiring/Heater | If an open circuit is found, repair the wiring or replace the heater if necessary. | Wiring Kit, Replacement Heater |
| Clear the Code and Test Drive | After completing repairs, clear the 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 P20C1 code does not reappear. | OBD-II Scanner |
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