OBD Guide

P20B6

Reductant Metering Unit Heater Control Circuit Performance

P20B6 is an OBD-II diagnostic trouble code meaning: Reductant Metering Unit Heater Control Circuit Performance. Common causes: open or short circuit in the heater circuit, malfunction of the heating element of the injection unit. Estimated repair cost: $56–278.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$56–278 (est.)

Symptoms

  • Check Engine Light Is On
  • Reduced engine power
  • Increased fuel consumption
  • Possible starting problems in cold weather
  • AdBlue system error message on the dashboard

Causes

  • Open or short circuit in the heater circuit
  • Malfunction of the heating element of the injection unit
  • Problems with the heater circuit relay or fuse
  • SCR control module malfunction
  • Poor contact in heater circuit connectors

How to Fix

  1. Check heater circuit fuses and relays
  2. Check the integrity of wires and connectors
  3. Measure the resistance of the heating element
  4. Check the operation of the SCR control module
  5. If necessary, replace the AdBlue injection unit

Related codes

Error P20B6 by Vehicle Brand

FAQ

What does the P20B6 code mean?

P20B6 is an OBD-II diagnostic trouble code that indicates: Reductant Metering Unit Heater Control Circuit Performance

What causes a P20B6 error code?

The most common causes of P20B6 include: Open or short circuit in the heater circuit; Malfunction of the heating element of the injection unit; Problems with the heater circuit relay or fuse; SCR control module malfunction.

How do I fix a P20B6 diagnostic trouble code?

To fix P20B6: Check heater circuit fuses and relays. Check the integrity of wires and connectors. Measure the resistance of the heating element. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P20B6?

Yes, but get it checked soon

How much does it cost to fix P20B6?

The estimated repair cost for P20B6 is $56–278. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat