OBD Guide

P1604

Loss Of IPC Serial Data Conditions

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$6–56 (est.)

Symptoms

  • Some indicators on the dashboard do not work
  • Speedometer or tachometer does not function
  • The Check Engine light comes on
  • No dashboard backlight
  • Problems with the on-board computer

Causes

  • Broken or damaged wires between the ECU and IPC
  • Corrosion of contacts in connectors
  • Instrument cluster malfunction
  • Dashboard power problems
  • Failures in ECU software

How to Fix

  1. Check the integrity of the wiring between the ECU and IPC
  2. Clean and check all connections
  3. Instrument cluster power diagnostics
  4. Check the operation of the dashboard
  5. Update or reflash the ECU software

Related codes

Error P1604 by Vehicle Brand