OBD Guide

P3002

HV ECU Communication Malfunction

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

Symptoms

  • Check Engine light comes on
  • The car goes into emergency mode
  • Reduced engine power
  • Problems with charging a high-voltage battery
  • Inability to start the hybrid system

Causes

  • Malfunction of the high voltage control unit (HV ECU)
  • Damage to the CAN bus wiring harness
  • Poor contact in connectors
  • Control unit power supply problems
  • Corrosion or oxidation of contacts

How to Fix

  1. Check the condition of the wiring harness and connectors
  2. Check power and grounding of HV ECU
  3. Scan other modules for communication errors
  4. If necessary, replace the high-voltage control unit
  5. Repair only from an authorized dealer

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