P20B7

Reductant Metering Unit Heater Control Circuit Low

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$56–167 (est.)

Symptoms

Check Engine Light Is On
Possible SCR System Error Message
Reduced engine power in cold weather
Increased fuel consumption
Increased NOx emissions

Causes

Open or short circuit in the heater circuit
Poor contact in control circuit connectors
Module heating element malfunction
Problems with the SCR control unit
Contact corrosion due to reagent exposure

How to Fix

Check the integrity of the wiring and contacts in the heater circuit
Measure the resistance of the heating element
Check the voltage at the module connectors
If necessary, replace the reagent dosing module
Reset the error code and test run the system

Related codes

P20B8 P20B9 P20BA