Code result

P223B

Reductant Heater F Control Circuit

High severity

What it means

Reductant Heater F Control Circuit: the control circuit has an electrical fault. The reductant (DEF/AdBlue) heater keeps the urea fluid from freezing; a fault can impair SCR dosing in cold conditions.

Is it safe to drive?

No — stop driving

This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.

Most likely causes

  • Heater winding or wiring fault

    high

    One of the most commonly reported causes for this code — check this first.

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