Clio MK2 1.2 16v - Radiator fan comes on full speed as soon as engine started

Anyone come across this before? As soon as i start the ignition the radiator fan comes on full speed. - Ac is turned off and makes no difference if i turn it on.

Coolant temp appears to be reading correct, starting at ambient temp and working its way up as the engine warms up.



Coolant temp guage reads correct, starting at 0 and working its self up as it heats up


ECU is commanding the 2nd stage fan to be on


And lastly, no fault codes logged!

Ac pressure sensor connected? Im sure that also puts fan on full belt.

Brigsy said:

Ac pressure sensor connected? Im sure that also puts fan on full belt.

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Corroded plug too.

Yep possibly bad wiring to the plug. On my dci i noticed the wiring was bare to the pressure switch for 20mm or so and corroded to fcuk. Still worked suprisingly, depinned connector and repaired it before issues.

Brigsy said:

Ac pressure sensor connected? Im sure that also puts fan on full belt.

Click to expand...

I bet that's it, the cars had a new radiator at some point and the cheapskate has just removed the condenser and chopped the pipes (I've got replacements of course 😂 ) so there's no gas in the system but I did notice the AC pressure sensor was reading something stupid like 20 bar!

will investigate tomorrow cheers.