P0117: Engine Coolant Temperature Sensor Circuit Low
11 vehicles · 10 makes · $150-$7,000 repair
Most Reported On
P0117 is an OBD-II diagnostic trouble code meaning “Engine Coolant Temperature Sensor Circuit Low.” This code means the engine coolant temperature (ECT) sensor is reading too low a voltage, which the computer interprets as an impossibly high coolant temperature. In most cases this is an electrical fault — such as a short to ground in the wiring — rather than the engine actually overheating. The coolant temperature signal affects fuel mixture, cooling fans, and other functions, so a bad reading can cause poor running, hard starting, or fans running constantly. The fault is usually in the sensor or its wiring. This code is most commonly reported on 2009-2019 Ford Flex, 2012-2020 Chevrolet Sonic, and 2008-2024 MINI John Cooper Works, plus 8 other vehicles, with repair costs ranging from $150 to $7,000.
Common Causes
Typical Repair Cost
Based on 11 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose P0117, you'll need an OBD-II scanner. Here are our recommendations at every price point.
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
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)
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
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
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
Vehicles Affected (11)
FAQ
What does P0117 mean?
P0117 stands for "Engine Coolant Temperature Sensor Circuit Low." This code means the engine coolant temperature (ECT) sensor is reading too low a voltage, which the computer interprets as an impossibly high coolant temperature. In most cases this is an electrical fault — such as a short to ground in the wiring — rather than the engine actually overheating. The coolant temperature signal affects fuel mixture, cooling fans, and other functions, so a bad reading can cause poor running, hard starting, or fans running constantly. The fault is usually in the sensor or its wiring.
What are the most common causes of P0117?
The most common causes of P0117 are: Faulty engine coolant temperature sensor, Short to ground in the sensor signal wire, Damaged or corroded wiring/connector at the sensor, Coolant contamination affecting the sensor, Poor electrical ground, Faulty PCM/ECM (less common). The specific cause varies by vehicle.
How much does it cost to fix P0117?
Repair costs for P0117 range from $150 to $7,000, depending on the vehicle and root cause.
Which vehicles are affected by P0117?
Au7o has documented P0117 across 11 vehicle models from 10 manufacturers: Cadillac, Chevrolet, Chrysler, Dodge, Ford, MINI, Nissan, Subaru, Toyota, Volvo.
Sources (10)
- owner-reportHow A Bad Water Pump Design Can Total A Ford Flex — The Autopian
- owner-reportChevrolet Sonic Common Problems - Samarins
- owner-reportMINI JCW Water Pump Replacement — MiniF56.com
- owner-reportCommon R56 MINI Problems — JCW Adventures
- mediaSubaru Model Years Worst Affected By Head Gasket Problems - Jalopnik
- ForumEJ25 head gasket failure inevitable - Subaru Forester Owners
- mediaSubaru Head Gasket Problems - Mechanic Base
- mediaChrysler Neon 2.0L Engine Repair - AA1Car
- mediaDodge Neon Blown Head Gasket Symptoms - Drivetrain Resource
- videoEricTheCarGuy - Ford Windstar 3.8L Intake Manifold Gasket Replacement
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.