Engine Coolant Level Sensor
A float or conductivity probe in the expansion tank reporting whether coolant remains above a minimum. It is the only thing on the vehicle able to detect that coolant has left the system, because the temperature gauge cannot: a temperature sensor uncovered by a falling level sits in air and steam and reads what the air pocket is doing, not what the metal is doing. That is why a low level can produce a normal-looking gauge on an engine that is overheating. Fails by sticking — deposits from topping up with tap water seize the float and insulate the probe — and the reading it sticks at is usually 'full'.
Also known as: coolant level switch, coolant level float, low coolant sensor, expansion tank sensor, coolant probe
Referenced by 15 codes
Codes involving this component (15)
- P2560 Engine Coolant Level Low Stop driving Critical
- P2556 Engine Coolant Level Sensor/Switch Circuit High
- P2557 Engine Coolant Level Sensor/Switch Circuit Range/Performance High
- P2558 Engine Coolant Level Sensor/Switch Circuit Low High
- P2559 Engine Coolant Level Sensor/Switch Circuit High High
- P2BE0 Hybrid/EV Battery Coolant Level Sensor Circuit/Open High
- P26CE Engine Coolant Pump Overspeed/Air In System
- P26FA Coolant Pump C Overspeed/Air in System
- P2B2A Hybrid/EV Electronics Coolant Pump A Overspeed — Dry Run
- P2B65 Coolant Pump B Overspeed/Air in System
- P2B6C Coolant Pump D Overspeed/Air in System
- P2B86 Coolant Pump A Overspeed/Air in System
- P2BE1 Hybrid/EV Battery Coolant Level Sensor Range/Performance
- P2BE2 Hybrid/EV Battery Coolant Level Sensor Circuit Low
- P2BE3 Hybrid/EV Battery Coolant Level Sensor Circuit High
Other components in Cooling
- Electric Coolant Pump 149
- Engine Coolant Temperature Sensor 105
- Engine Coolant Flow Control Valve 82
- Radiator 61
- Active Grille Shutter Module 53
- Engine Coolant Bypass Valve 42
- Thermostat 40
- Cooling Fan 40
- 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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