A valve assembly failsafe configured to be coupled to an actuator of a coolant control regulator assembly is provided. The valve assembly failsafe includes a wind arm, a spring that engages the wind arm under spring tension, a latch that engages the wind arm, a drive gear that engages the wind arm and the actuator, and a driver that engages the latch. The valve assembly failsafe is configured to be positioned in a set state where the latch engages and retains the wind arm under spring tension and the drive gear freely rotates during rotation of the actuator, and a tripped state where the driver rotates the latch to disengage the latch from the wind arm, causing the wind arm to rotate under the spring tension to engage the drive gear and cause the drive gear to drive the actuator to a default position.

A method is provided for operating a cooling system of an internal combustion engine, which cooling system has a controllable rotary slide valve with at least one switched inlet or outlet. The movement of the rotary slide valve into a plurality of switching positions, which each correspond with a cooling system state, is monitored. In accordance with an improper functional state of the rotary slide valve and a current switching position of the rotary slide valve, an operating state of the internal combustion engine is changed to an emergency operation state. A protection system in the cooling system carries out the method and includes a thermal management system, which receives and processes coolant temperatures, and a control unit of a controllable rotary slide valve having a position detector, which can detect a current switching position of the switchable rotary slide valve, wherein the thermal management system is connected to the control unit of the rotary slide valve.

Methods and systems are providing for improving engine coolant level estimation to reduce engine overheating. The level of fluid in a coolant overflow reservoir is inferred based on the fluid level in a hollow vertical standpipe fluidically coupled to the reservoir at top and bottom locations, while the fluid level in the standpipe is estimated based on echo times of an ultrasonic signal transmitted by a sensor positioned in a recess at the bottom of the vertical standpipe. Engine power is limited differently based on distinct coolant level states determined based on a change in level of coolant in the reservoir over a duration.

A refrigerant control valve apparatus includes a valve body provided with a main control valve controlling the refrigerant sent to a discharge port and a temperature sensing control valve controlling supply and discharge of the refrigerant to a temperature sensing chamber. A fail-safe mechanism is provided which supplies the refrigerant to the discharge port in a case where the temperature of the refrigerant exceeds a set value. The temperature sensing control valve is set in an open posture in a case where the main control valve is in a closed posture that closes the discharge port and the temperature sensing control valve is set in a closed posture in a case where the main control valve is in an open posture that opens the discharge port.

A diagnostic apparatus for a coolant control valve including a housing having a plurality of ports, a valve member provided to be rotatable in the housing, and a driving device rotating the valve member between two end positions, the diagnostic apparatus including at least one position sensor provided on an external surface of the housing for sensing a position of the valve member, a determination device for determining whether or not the valve member is stuck using the position of the valve member sensed by the position sensor and a controller for controlling the driving device.

Cooling control systems described herein detect decreased operation of a cooling system of a vehicle, restrict movement of the vehicle without stopping movement responsive to decreased operation of the cooling system, and restrict movement of the vehicle by preventing the vehicle from traveling at a speed and/or power output for a non-zero designated period of time. This can allow for the vehicle to continue moving for a temporary period of time to avoid blocking traffic. Other control systems determine predicted distances and/or times that the vehicle can continue moving before coolant in the cooling system decreases below a designated threshold. Movement of the vehicle can be changed responsive to an upcoming distance and/or time that the vehicle is to travel exceeding the predicted distance and/or time. Other control systems modify a coolant flow rate based on differences between designated and ambient conditions.

Methods and systems are providing for improving engine coolant level estimation to reduce engine overheating. The level of fluid in a coolant overflow reservoir is inferred based on the fluid level in a hollow vertical standpipe fluidically coupled to the reservoir at top and bottom locations, while the fluid level in the standpipe is estimated based on echo times of an ultrasonic signal transmitted by a sensor positioned in a recess at the bottom of the vertical standpipe. Engine power is limited differently based on distinct coolant level states determined based on a change in level of coolant in the reservoir over a duration.

Methods and systems are providing for improving engine coolant level estimation to reduce engine overheating. The level of fluid in a coolant overflow reservoir is inferred based on the fluid level in a hollow vertical standpipe fluidically coupled to the reservoir at top and bottom locations, while the fluid level in the standpipe is estimated based on echo times of an ultrasonic signal transmitted by a sensor positioned in a recess at the bottom of the vertical standpipe. Engine power is limited differently based on distinct coolant level states determined based on a change in level of coolant in the reservoir over a duration.

A method is provided for operating a cooling system of an internal combustion engine, which cooling system has a controllable rotary slide valve with at least one switched inlet or outlet. The movement of the rotary slide valve into a plurality of switching positions, which each correspond with a cooling system state, is monitored. In accordance with an improper functional state of the rotary slide valve and a current switching position of the rotary slide valve, an operating state of the internal combustion engine is changed to an emergency operation state. A protection system in the cooling system carries out the method and includes a thermal management system, which receives and processes coolant temperatures, and a control unit of a controllable rotary slide valve having a position detector, which can detect a current switching position of the switchable rotary slide valve, wherein the thermal management system is connected to the control unit of the rotary slide valve.

The present invention relates to a method for protecting an engine from short circuiting and wire failure of a fan clutch, and a device thereof wherein the method for protecting an engine comprises: a step of sensing the temperature of a coolant if a fan rotates at a set minimum rpm by the short circuiting and wire failure of a fan clutch; a step of comparing the sensed coolant temperature and a set danger temperature; and a step of defaulting if the sensed coolant temperature is lower than the set danger temperature and reducing the engine rpm if the sensed coolant temperature is equal to or higher than the set danger temperature according to a result of the comparison such that overheating of the engine can be prevented. The engine rpm is gradually lowered so as to protect the engine at a first stage if the fan operates at the minimum rpm due to the cable short cut and failure of the fan clutch, and the engine is forcedly stopped so as to protect the engine at a second stage if the overheating of the coolant is serious, thereby ensuring durability of the engine.