U01A4

Lost Communication With Hybrid/EV Battery Interface Control Module E

Severity

🔴 High

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$167–556 (est.)

Symptoms

Check Engine light comes on
Loss of engine power
The car goes into emergency mode
Cannot charge high voltage battery
Error message on the dashboard

Causes

CAN bus break or damage
Problems with power supply to the battery management module
Malfunction of the battery management module itself
Corrosion or poor contact in connectors
Software error in one of the modules

How to Fix

Check the integrity of the CAN bus and connections between modules
Check power and grounding of the battery management module
Scan all modules for additional error codes
Diagnose the battery control module
If necessary, replace the battery management module
Repair only from an authorized dealer

Related codes

U01A0 U01A1 U01A2