Code result
P20B3
Reductant Heater Coolant Control Valve Circuit Low
Moderate severity
What it means
This code indicates reductant heater coolant control valve circuit low. It relates to the emissions: nox, particulate, dpf, scr and may affect performance, emissions, or drivability depending on the exact failure.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Sensor failure
mediumO2, NOx, pressure, or temperature sensors can drift or fail.
Exhaust leak or restriction
mediumLeaks before sensors or a restricted exhaust can set emissions codes.
Wiring or connector fault
mediumCorrosion or damage in the sensor circuit is a common cause.
Related help
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