P20BC

Reductant Heater A Control Circuit High

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$33–167 (est.)

Symptoms

Check Engine light comes on
Possible reduction in engine power
Increased emissions of nitrogen oxides (NOx)
SCR system error message on dashboard
Problems starting in cold weather

Causes

Short circuit in the heater circuit
Heating element malfunction
Problems with the SCR control module
Broken or damaged wiring harness
Corrosion of contacts or connectors

How to Fix

Check the integrity of the heater wiring harness
Measure the resistance of the heating element
Check the voltage at the heater connectors
Inspect connectors for corrosion
If necessary, replace the heating element or wiring harness

Related codes

P20BD P20B9 P20BA