OBD Guide

U1846

Drive Motor Control Module 2 Lost Communication With Hybrid/EV Powertrain Control Module

U1846 is an OBD-II diagnostic trouble code meaning: Drive Motor Control Module 2 Lost Communication With Hybrid/EV Powertrain Control Module. Common causes: broken or damaged can bus wires, engine control module malfunction. Estimated repair cost: $56–333.

Severity
🔴 High
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–333 (est.)

Symptoms

  • Check Engine Light Is On
  • The hybrid system goes into emergency mode
  • Reduced power or efficiency
  • Battery charging/discharging problems

Causes

  • Broken or damaged CAN bus wires
  • Engine control module malfunction
  • Malfunction of the hybrid transmission control module
  • Problems with power supply or grounding of modules
  • Corrosion of connectors

How to Fix

  1. Checking the integrity of the CAN bus wiring
  2. Engine control module diagnostics
  3. Diagnostics of the hybrid transmission control module
  4. Checking connectors and contacts for corrosion
  5. Testing power supply and grounding of modules

Related codes

FAQ

What does the U1846 code mean?

U1846 is an OBD-II diagnostic trouble code that indicates: Drive Motor Control Module 2 Lost Communication With Hybrid/EV Powertrain Control Module

What causes a U1846 error code?

The most common causes of U1846 include: Broken or damaged CAN bus wires; Engine control module malfunction; Malfunction of the hybrid transmission control module; Problems with power supply or grounding of modules.

How do I fix a U1846 diagnostic trouble code?

To fix U1846: Checking the integrity of the CAN bus wiring. Engine control module diagnostics. Diagnostics of the hybrid transmission control module. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U1846?

Limited driving only, diagnose soon

How much does it cost to fix U1846?

The estimated repair cost for U1846 is $56–333. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat