OBD Guide

P1118

Engine Coolant Temp Signal Out-Of Range High

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$6–33 (est.)

Symptoms

  • Incorrect temperature readings on the dashboard
  • Engine overheating
  • Increased fuel consumption
  • Unstable engine idling
  • Difficulty starting the engine

Causes

  • Coolant temperature sensor malfunction
  • Open or short circuit in the sensor circuit
  • Poor contact in sensor connectors
  • Problems with the ECU
  • Low coolant level

How to Fix

  1. Check the level and condition of the coolant
  2. Check the integrity of the sensor wires and connectors
  3. Test coolant temperature sensor (resistance)
  4. Replace the coolant temperature sensor if necessary
  5. Check error codes after repair and make sure they are absent

Related codes

Error P1118 by Vehicle Brand