overheat warning fan not running

gfromleeds wrote:Well as promised an update

Thanks for the update

gfromleeds wrote:Now I read that the C3 holds 7 litres but only 2or3 came out
how would I get the rest out to do a complete flush?

Sounds like you only got the coolant from one side of the thermostat. There is a drain point somewhere on the lower part of the radiator and you can unscrew the various bleed points to allow the air in. Disconnecting some of the cooling pipes is sure to help.

You could flush the system out with clean water and a hose pipe if its looking a mess.

Then refill with the right coolant - see (the right coolant for a Citroen C3) and bleed all that air out afterwards.

Well it turns out the problems not fixed as it overheated again today
Although as I was sat in the middle lane of the m62 in very slow traffic I couldn't switch off so I cranked the blowers up and turned the heater up full in a desperate attempt to cool it down and within 15 seconds the warning turned off again!
So it's clear the problem is just getting rid of the heat so.
Until I get to the root cause is there any way I could wire a dash switch to override the radiator fan to be manual thus if I find myself in this situation again I could manually turn the radiator fan on and no need for such a panic

gfromleeds wrote:Until I get to the root cause is there any way I could wire a dash switch to override the radiator fan to be manual thus if I find myself in this situation again I could manually turn the radiator fan on and no need for such a panic

I don't see why not. You have good access to the fan speed terminals if you have this fan:

C3driver52 wrote:The diesel has a 3 pin plug. One wire (white) always read 12v to battery earth (its fed from the BSI), Yellow didn't read anything (fed from the Engine ECU) and the pinky purple one (fed from the Engine ECU) measured 8v (to battery earth) which decreased as the fan slowed down. Its highly possible the pinky purple was more than 8v before I managed to look at the meter, so Its probably 12V for full fan speed.

https://citroenc3owners.com/petrol-citro ... -t400.html

They were different colours on mine I have white, off white and blue (off white could had been faded yellow) complete cut on one on the white wires overrides the fan and runs it at full speed

gfromleeds wrote:complete cut on one on the white wires overrides the fan and runs it at full speed

That's your circuit then. The switch makes or breaks that wire. If its a fat (heavy current carrying) wire, you should run via a relay and the switch on the dashboard operates the relay.

No its only a thin wire but the strange thing is if I let it get hot 2-3 degrees before the warning then flick the switch to turn the fan on it doesn't come on?
I'm starting to think maybe the fault is the fan itself? Is that possible? heat related/causing a break in the cicuit?
I'm starting to get pi$$ on with this now and thinking of just ripping the fan out replacing it with a simple one speed aftermarket fan and straoght forward on/off thermostat