P20B1

Reductant Heater Coolant Control Valve Circuit/Open

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$28–89 (est.)

Symptoms

Check Engine Light Is On
Possible reduction in engine power
SCR system fault message
Increased consumption of AdBlue reagent
Problems starting in cold weather

Causes

Open or short circuit in valve circuit
Heater solenoid valve malfunction
Relay or fuse problems
SCR control unit malfunction
Corroded contacts or damaged wiring harness

How to Fix

Check heater circuit fuses and relays
Inspect the wiring harness for damage
Check valve resistance and operation
Scan the SCR control unit for additional errors
Replace the faulty valve or repair the wiring

Related codes

P20A0 P20EE P20B9