U01A1 Lost Communication With Hybrid/EV Battery Interface Control Module B

Common causes

• Most likelyModule unpowered
• Less likelyGateway module routing CAN messages incorrectly
• Less likelyCAN terminating resistor (120 Ω) drifted out of spec

Symptoms

• Multiple warning lights may illuminate
• Affected modules may go into limp mode or shut down
• Specific functions inoperative depending on module
• Diagnostic tools may show communication faults

Repair at a glance

Difficulty

Hard

DIY friendly

Best left to a mechanic

Typical labour

1–8 h

Emissions test

Usually unaffected

After the fix

A drive cycle is needed before the light stays off

Parts involved

Hv Battery Interface B, Can Bus

Related codes

• U01A0Lost Communication With Hybrid/EV Battery Interface Control Module A
• U01A2Lost Communication With Hybrid/EV Battery Interface Control Module C
• U01A3Lost Communication With Hybrid/EV Battery Interface Control Module D
• U01A4Lost Communication With Hybrid/EV Battery Interface Control Module E
• U01A5Lost Communication With Hybrid/EV Battery Interface Control Module F
• U01A6Lost Communication With Hybrid/EV Battery Interface Control Module G
• U01A7Lost Communication With Hybrid/EV Battery Interface Control Module H
• U01A8Lost Communication With Hybrid/EV Battery Interface Control Module I
• U01A9Lost Communication With Hybrid/EV Battery Interface Control Module J
• U01AALost Communication With Hybrid/EV Battery Interface Control Module K
• U01ABLost Communication With Hybrid/EV Battery Interface Control Module L
• U01ACLost Communication With Hybrid/EV Battery Interface Control Module M
• U019ELost Communication With Transmission Range Control Module
• U019FLost Communication With Engine Coolant Pump Control Module