Engine Coolant Temperature Sensor
Drives more decisions than almost any other sensor: cold-start enrichment, when closed-loop fuelling begins, and cooling fan operation. Many vehicles carry two — one for the control module and one for the gauge — so a working temperature gauge does not rule out a fault here.
Also known as: ect, ect sensor, coolant temp sensor, water temp sensor, cts, coolant temperature sender, cts sensor
Referenced by 105 codes
Codes involving this component (105)
- P0217 Engine Coolant Over Temperature Condition Stop driving Critical
- P2560 Engine Coolant Level Low Stop driving Critical
- P0115 Engine Coolant Temperature Sensor 1 Circuit High
- P0117 Engine Coolant Temperature Sensor 1 Circuit Low High
- P0118 Engine Coolant Temperature Sensor 1 Circuit High High
- P0483 Cooling Fan Rationality Check High
- P2601 Coolant Pump A Control Circuit Performance/Stuck Off High
- P26AB Engine Coolant Bypass Valve A Stuck/Open High
- P2B61 Engine Coolant Flow Control Valve Stuck Closed Stop driving High
- P0116 Engine Coolant Temperature Sensor 1 Circuit Range/Performance Moderate
- P0119 Engine Coolant Temperature Sensor 1 Circuit Intermittent/Erratic Moderate
- P011B Engine Coolant Temperature/Intake Air Temperature Correlation Moderate
- P0125 Insufficient Coolant Temperature for Closed Loop Fuel Control Moderate
- P0126 Insufficient Coolant Temperature for Stable Operation Moderate
- P0128 Coolant Thermostat — Temperature Below Regulating Point Moderate
- P015E Excessive Time to Enter Closed Loop Fuel Timing Control Moderate
- P01D0 Cylinder 3 Injection Timing Performance - Over Advanced Moderate
- P0316 Engine Misfire Detected on Startup (First 1000 Revolutions) Moderate
- P050A Cold Start Idle Control System Performance Moderate
- P0655 Engine Hot Lamp Output Control Circuit Moderate
- P2181 Cooling System Performance Moderate
- P2182 Engine Coolant Temperature Sensor 2 Circuit Moderate
- P2183 Engine Coolant Temperature Sensor 2 Circuit Range/Performance Moderate
- P2184 Engine Coolant Temperature Sensor 2 Circuit Low Moderate
- P2185 Engine Coolant Temperature Sensor 2 Circuit High Moderate
Other components in Cooling
- Electric Coolant Pump 149
- Engine Coolant Flow Control Valve 82
- Radiator 61
- Active Grille Shutter Module 53
- Engine Coolant Bypass Valve 42
- Thermostat 40
- Cooling Fan 40
- Engine Coolant Level Sensor 15
- Water Pump 12
- Radiator Coolant Temperature Sensor 11
- Coolant Expansion Tank 8
- Fuel Fired Heater 5
- Coolant Degassing Valve 3
- Oil Cooler 1
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