U01A0

Lost Communication With Hybrid/EV Battery Interface Control Module A

Severity

🚨 Critical

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$56–278 (est.)

Symptoms

Check Engine light comes on
Reduced vehicle power
Switching to emergency mode
Inability to charge the battery
Displaying warnings on the instrument panel

Causes

Open or short circuit in the CAN bus
Battery management module malfunction
Problems with module power supply (blown fuse)
Corroded or damaged connectors
Software error in control module

How to Fix

Check fuses associated with the battery control module
Inspect connectors and wiring harness for damage
Conduct CAN bus diagnostics using an oscilloscope
Read error codes from the battery management module
Update or reflash module software
Repair only from an authorized dealer

Related codes

U01A1 U0100 U0121