OBD Guide

U0178

Lost Communication With Restraints System Sensor I

Severity
🔴 High
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$56–167 (est.)

Symptoms

  • SRS/Airbag light is on
  • Security error message on display
  • Airbags may not deploy in a crash
  • Seat belt pretensioners do not work
  • The system may log additional related codes

Causes

  • Broken or damaged wiring to the sensor
  • Oxidation of contacts in security system connectors
  • Malfunction of the security system sensor itself
  • Problems with the SRS control unit
  • Short circuit in the sensor circuit

How to Fix

  1. Carry out diagnostics with a scanner that supports the SRS system
  2. Check the integrity of the wiring and connectors of the sensor
  3. Measure the resistance and voltage in the sensor circuit
  4. If necessary, replace the security sensor
  5. Repair only from an authorized dealer

Related codes

Error U0178 by Vehicle Brand