Cooling fan not kicking in

[Macchiman]

The car, 2007 Sigma 1.6 SV,  has been having intermittent overheating issues.  The cooling fan sometimes kicks in and sometimes doesn't.  I have changed the fan relay, but still having issues.  I guess it must be the coolant temp sensor, which seems to be located at the rear of the block underneath the coil pack.  Is this correct?  Any thoughts on the issue?  Thanks.

[Jonathan Kay]

Would you like a copy of the wiring diagram? Do you have a multimeter?

Is the radiator fan on your Seven controlled by its own circuit or by the ECU?

Check all of the relevant connections to the fan and sensors: inspect, wiggle, disconnect, clean, reconnect.

You can probably test what's happening without waiting for the engine to warm up and cool down by disconnecting and shorting to earth the lead(s) to the sensors.

Jonathan

[Macchiman]

A wiring diagram may help, I have a multimeter. How can I check if the fan is controlled by the ECU or its own circuit?  I had the engine upgraded to Jenveys and a new MBE 9A4B ECU some years ago.

[Jonathan Kay]

Please send me a Private Message with your email address.

Jonathan

[SM25T]

Our k-series has a thermo switch fitted in the header tank at the top of the radiator. This starts and stops the fan. Maybe yours is switched by the ECU ?