Citroen C4 automatic. After car has been driving then stops, the fan keeps going until battery runs dead. The AA fitted brand new battery but problem persists. Any ideas?
Most "CCC" Or computer comand controlled vehicles supply power to the electircal components automaticaly via a relay, there will be one power source with the ignition off,& a second power sourse when the ignition is turned on,In this case the temp sensor will supply a ground to the cooling fan circuit when the engine temp reaches a specified temperature and the fan comes on. In my opinion you most likely have a relay that has malfunctioned(gotten too hot & fused internaly) find your engine cooling fan relay(s) & remove them.If the fan stops you may have found your problem.to check the power supplied to the relay you will need a simple test light, connect the clip to a good ground & probe the relay socket with the tip of the lights probe. where there is power the test light will light up. Ignition off-1 power source,Ignition on-2 power sources/ to check for the ground supplied by the temp sensor connect the test lights clip to a battary+ source & probe the relay socket again if there is a ground supplied the test light will light up, there may be more than one temp sensor in the cooling system.you should be able to aquir a wiring diagram online if you do not have a book.one of the sensors sends the temp signal to the gauge in the dash, & the other is the ground supply for thr fan relay. I hope I have been of some help.