U01B5

Lost Communication With Catalyst Heater Control Module

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$56–167 (est.)

Symptoms

Check Engine Light Is On
Reduced catalytic converter efficiency
Possible problems starting the engine in cold weather
Increased fuel consumption
Reduced engine power

Causes

Open or short circuit in the heating module circuit
Malfunction of the catalyst heating control module
Module power problems
Faulty relay or fuse
ECU problems (rare)

How to Fix

Check the integrity of fuses and relays associated with the system
Check the condition of the wiring harness and module connectors
Check the power supply and ground of the heating module
Test the catalyst heating module
If necessary, replace the heating module

Related codes

U01B4 U01B6 U01B7