P20B5
Reductant Metering Unit Heater Control Circuit/Open
P20B5 is an OBD-II diagnostic trouble code meaning: Reductant Metering Unit Heater Control Circuit/Open. Common causes: open or short circuit in the heater circuit, dosing unit heater malfunction. Estimated repair cost: $56–167.
Symptoms
- Check Engine Light Is On
- Reduced engine power
- Increased fuel consumption
- Increased NOx emissions
- Possible starting problems in cold weather
Causes
- Open or short circuit in the heater circuit
- Dosing unit heater malfunction
- Relay or fuse problems
- SCR control module malfunction
- Poor contact in connectors
How to Fix
- Check the integrity of the heater circuit
- Check the resistance of the heating element
- Inspect connectors and wiring for damage
- Check fuses and relays
- If necessary, replace the reagent dosing unit
Related codes
Error P20B5 by Vehicle Brand
FAQ
What does the P20B5 code mean?
P20B5 is an OBD-II diagnostic trouble code that indicates: Reductant Metering Unit Heater Control Circuit/Open
What causes a P20B5 error code?
The most common causes of P20B5 include: Open or short circuit in the heater circuit; Dosing unit heater malfunction; Relay or fuse problems; SCR control module malfunction.
How do I fix a P20B5 diagnostic trouble code?
To fix P20B5: Check the integrity of the heater circuit. Check the resistance of the heating element. Inspect connectors and wiring for damage. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with P20B5?
Yes, but get it checked soon
How much does it cost to fix P20B5?
The estimated repair cost for P20B5 is $56–167. Actual cost depends on your vehicle, location, and labor rates.
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