ShopBaseFree forever shop management software for auto repair shops
Try ShopBase Free →
Home/DTC Codes/GMC/Envoy/2002-2009 4.2L I6/P0118
P0118

ECT Sensor 1 Circuit High Input

2002-2009 GMC Envoy 4.2L I6

High SeverityPowertrainGeneric (SAE)

Description

The ECT sensor voltage is higher than expected, indicating very low temperature or open circuit.

Symptoms

  • Check Engine Light
  • Rich running at operating temp
  • Poor fuel economy
  • Fans not coming on

Common Causes

  • Open circuit
  • Disconnected sensor
  • Faulty sensor
  • Corroded connector

Diagnostic Steps

  1. Test sensor resistance
  2. Check for open circuits
  3. Inspect connector

Repair Notes

Repair open circuit or replace sensor. CAUTION: Engine may overheat if fans do not activate.

Related Codes

P0115Engine Coolant Temperature (ECT) Sensor 1 CircuitP0117ECT Sensor 1 Circuit Low Input

Other Powertrain Codes

P0118 on Other Vehicles

GMC Acadia

2017-2024 2.5L I4

GMC Acadia

2017-2024 3.6L V6

GMC Canyon

2004-2012 2.8L I4

GMC Canyon

2004-2012 3.5L I5

GMC Canyon

2007-2012 2.9L I4

GMC Canyon

2007-2012 3.7L I5

GMC Canyon

2015-2022 2.8L I4 Duramax Diesel

GMC Canyon

2015-2022 3.6L V6

Common Questions

What does code P0118 mean on a 2002-2009 GMC Envoy?

P0118 stands for "ECT Sensor 1 Circuit High Input". The ECT sensor voltage is higher than expected, indicating very low temperature or open circuit.

What are the symptoms of P0118 on a GMC Envoy?

Common symptoms of P0118 include: Check Engine Light, Rich running at operating temp, Poor fuel economy, Fans not coming on.

What causes P0118 on a 2002-2009 GMC Envoy?

Common causes of P0118 include: Open circuit, Disconnected sensor, Faulty sensor, Corroded connector.

View Labor Times | View Torque Specs | View Fluid Specs