OBD Guide

U18B5

Lost Communication With Hybrid Powertrain Control Module On Chassis Expansion CAN Bus

U18B5 is an OBD-II diagnostic trouble code meaning: Lost Communication With Hybrid Powertrain Control Module On Chassis Expansion CAN Bus. Common causes: open or short circuit in the can bus, malfunction of the hybrid transmission control module. Estimated repair cost: $167–556.

Severity
🔴 High
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$167–556 (est.)

Symptoms

  • Hybrid system does not work
  • Check Engine light comes on
  • The car goes into emergency mode
  • Reduced engine power
  • Inability to charge the traction battery

Causes

  • Open or short circuit in the CAN bus
  • Malfunction of the hybrid transmission control module
  • Module power problems
  • Corroded or damaged connectors
  • Software error in the module

How to Fix

  1. Check the integrity of the CAN bus
  2. Check power supply and grounding of the module
  3. Inspect connectors for damage
  4. Scan the module for additional errors
  5. If necessary, replace the hybrid powertrain control module

Related codes

FAQ

What does the U18B5 code mean?

U18B5 is an OBD-II diagnostic trouble code that indicates: Lost Communication With Hybrid Powertrain Control Module On Chassis Expansion CAN Bus

What causes a U18B5 error code?

The most common causes of U18B5 include: Open or short circuit in the CAN bus; Malfunction of the hybrid transmission control module; Module power problems; Corroded or damaged connectors.

How do I fix a U18B5 diagnostic trouble code?

To fix U18B5: Check the integrity of the CAN bus. Check power supply and grounding of the module. Inspect connectors for damage. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U18B5?

Do not drive — repair immediately

How much does it cost to fix U18B5?

The estimated repair cost for U18B5 is $167–556. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat