U012F

Lost Communication With Generator B Control Module

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$22–167 (est.)

Symptoms

Check Engine Light Is On
Reduced charging system efficiency
Unstable operation of electrical equipment
Floating engine speed
Error message on the dashboard

Causes

Broken or damaged wires in the communication circuit
Generator control module B malfunction
Control module power problems
Short circuit in communication circuit
Software failure in the ECU

How to Fix

Check the integrity of the wiring harness to generator module B
Diagnose power and ground of the control module
Check communication with the module using a diagnostic scanner
Flash or replace generator control module B (if necessary)
Eliminate possible corrosion in connectors

Related codes

U012E U0130 U0121