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P0118MinorCooling

P0118: Engine Coolant Temperature Sensor Circuit High

7 vehicles · 5 makes · $100-$7,000 repair

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P0118 is an OBD-II diagnostic trouble code meaning “Engine Coolant Temperature Sensor Circuit High.” The coolant temperature sensor circuit is reading higher than expected. Open circuit or sensor failure. This code appears across 7 vehicle models from 5 manufacturers, with repair costs ranging from $100 to $7,000.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (7)
  • Related Codes
  • FAQ

Makes

  • Audi1
  • Cadillac1
  • Ford1
  • Subaru1
  • Toyota3
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Common Causes

1Faulty coolant temperature sensor
2Open circuit in wiring
3Corroded connector
4Disconnected sensor
5Damaged harness

Typical Repair Cost

$100 - $7,000

Based on 7 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P0118, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
Check Price on Amazon
Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
  • Repair Reports with verified fixes
  • Smog check readiness
  • Free app (iOS & Android)
Check Price on Amazon
Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
Check Price on Amazon
Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

  • All-system diagnostics (25+ modules)
  • Bi-directional control & active tests
  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
Check Price on Amazon

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (7)

S5Critical

EA839 Water Pump Internal Leak and Vacuum System Contamination (2.9T)

2018-2024$1,200-$3,5000 reports
SevilleCritical

Northstar 4.6L Head Gasket Failure (Head Bolt Thread Pull)

1996-2003$2,400-$4,5000 reports
FlexCritical

Internal Water Pump Failure Causes Coolant-Oil Mixing and Catastrophic Engine Damage

2009-2019$1,500-$7,000480 reports
ForesterCritical

EJ25 Head Gasket Failure (External Leak)

1998-2010$1,800-$3,5000 reports
Prius CCritical

Electric Water Pump Failure

2012-2019$400-$8000 reports
AvalonModerate

Water Pump Leak (2GR-FE/2GR-FKS 3.5L V6)

2005-2018$300-$1,0000 reports
SequoiaModerate

i-FORCE MAX Hybrid Cooling System Issues

2023-2025$100-$2,0000 reports

Related Codes (8)

P0117Engine Coolant Temperature Sensor Circuit LowP00B7Engine Coolant Flow Low/PerformanceP0128Coolant Thermostat Below Regulating TemperatureP0217Engine Overtemperature ConditionP0597Thermostat Heater Control Circuit OpenP0598Thermostat Heater Control Circuit LowP0599Thermostat Heater Control Circuit HighP0A93Inverter Cooling System Performance

FAQ

What does P0118 mean?

P0118 stands for "Engine Coolant Temperature Sensor Circuit High." The coolant temperature sensor circuit is reading higher than expected. Open circuit or sensor failure.

What are the most common causes of P0118?

The most common causes of P0118 are: Faulty coolant temperature sensor, Open circuit in wiring, Corroded connector, Disconnected sensor, Damaged harness. The specific cause varies by vehicle.

How much does it cost to fix P0118?

Repair costs for P0118 range from $100 to $7,000, depending on the vehicle and root cause.

Which vehicles are affected by P0118?

Au7o has documented P0118 across 7 vehicle models from 5 manufacturers: Audi, Cadillac, Ford, Subaru, Toyota.

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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