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Ross, Diagnostic and repair technician
Category: Car
Satisfied Customers: 1159
Experience:  Licensed diagnostic and repair technician
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I have a DS3 and today the cooling fan has been running

Customer Question

Hi, I have a DS3 and today the cooling fan has been running constantly, as I approached home, the engine autpdiagnosis light came on - any idea what's going on??
Submitted: 10 months ago.
Category: Car
Customer: replied 10 months ago.
The car is a 1.6Vti 16V 3-door petrol
Expert:  Ross replied 10 months ago.
Hi my name is***** am a diagnostic technician and look forward to working with you.It sounds like there is a fault on the engine management system, the diagnostic light will be on as a fault code has been stored in the memory. The fact the cooling fan is running constantly is actually completely normal operation when certain faults are detected, this is due to the engine going into safe mode to protect its self. e.g if the fault detected was with a temperature sensor, the fan will run constantly due to no temperature signal to control the fan automatically.Unfortunately due to the complexity of modern engine electronics it is impossible for me to give a specific cause. There are hundreds of possible causes of this and the only way to find out is to plug the car into a diagnostic scanner which will show a fault code and description of the fault. This will pinpoint the cause of the symptoms. Often it is a simple sensor problem so is by no means a necessarily a major problem and it can even be a glitch that simply needs re-setting.The next step is to get the car scanned, any good garage can do this, it usually starts at around £40, there is no need to take it to a main dealer, however if you choose to it can costs up to £100. The garage will usually tell you exactly what caused the problem and advise on the best remedy. e.g a faulty temp sensor which is a common cause of this will cost around £50 plus half an hour to fit. Occasionally faults are a little more complex such as wiring problems, although this is unlikely in your case it may need a little more time to find the problem.If there are no other running issues, and just these symptoms the car will be perfectly safe to use until you can conveniently get it looked at. I hope I’ve provided the information you were seeking. If you need more help, please use the reply tab to continue our conversation. If you do not require further assistance, kindly rate my service. Thank you, Ross.

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