OBD Guide

U179C

Lost Communication With One Or More Hybrid/EV Battery Interface Control Modules

U179C is an OBD-II diagnostic trouble code meaning: Lost Communication With One Or More Hybrid/EV Battery Interface Control Modules. Common causes: open or short circuit in the communication circuit, problems with power supply to the battery management module. Estimated repair cost: $56–278.

Severity
🔴 High
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$56–278 (est.)

Symptoms

  • Check Engine light comes on
  • The car goes into emergency mode
  • Reduced power or inability to start
  • Errors in the hybrid/electric powertrain system
  • Inability to charge the battery

Causes

  • Open or short circuit in the communication circuit
  • Problems with power supply to the battery management module
  • Malfunction of the battery management module itself
  • Wiring harness damage
  • Problems with the CAN bus

How to Fix

  1. Check the integrity of the wiring harness to the battery control module
  2. Check the module supply voltage
  3. Scan all modules for additional fault codes
  4. Check CAN bus connections
  5. Test or replace the battery management module

Related codes

FAQ

What does the U179C code mean?

U179C is an OBD-II diagnostic trouble code that indicates: Lost Communication With One Or More Hybrid/EV Battery Interface Control Modules

What causes a U179C error code?

The most common causes of U179C include: Open or short circuit in the communication circuit; Problems with power supply to the battery management module; Malfunction of the battery management module itself; Wiring harness damage.

How do I fix a U179C diagnostic trouble code?

To fix U179C: Check the integrity of the wiring harness to the battery control module. Check the module supply voltage. Scan all modules for additional fault codes. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U179C?

Do not drive — repair immediately

How much does it cost to fix U179C?

The estimated repair cost for U179C is $56–278. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat