Patent ID: 6763709
Filing Date: 2004-07-20
Classification: F01P

Abstract:
A vehicle comprising a cooling circuit including a thermostat arranged in use to control the flow of a coolant around at least a part of the cooling circuit, the vehicle further comprising a control means arranged in use to carry out an on-board fault detection test routine to establish the operational condition of the thermostat, the test routine being arranged to determine the condition of the thermostat from a comparison between a thermostat inlet temperature and a thermostat outlet temperature and to determine that the thermostat is faulty if the thermostat inlet temperature is below an opening temperature of the thermostat and there is a temperature differential between the thermostat inlet temperature and the thermostat outlet temperature which differential is below a predetermined fault threshold, the cooling circuit further comprising a radiator and the thermostat being arranged in use to control the flow of the coolant through the radiator, characterised in that the thermostat inlet temperature is derived from a top hose or radiator inlet temperature and/or the thermostat outlet temperature is derived from a bottom hose or radiator outlet temperature.