U066C

Lost Communication With Exhaust Heat Exchanger Bypass Valve Actuator B

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$28–89 (est.)

Symptoms

Check Engine light comes on
Deterioration of interior heating in cold weather
Increased fuel consumption
Unstable engine operation when cold

Causes

Open or short circuit in valve circuit
Solenoid valve malfunction
Problems with the connector or wiring harness
Engine control unit malfunction
Contact corrosion

How to Fix

Check valve control circuit integrity
Check the resistance and operation of the solenoid valve
Inspect connectors and wiring harness for damage
Clean contacts from corrosion
Replace valve if necessary

Related codes

U066B U066D U066E