It sounds like an issue, possibly with the sensor or wiring to it.

The sensor is normally on the expansion tank

You should be able to look it up, here, Peugeot (ssg.asia)

Example:

 

OK great, that was my line of thinking also. I will change the sensor and report back. Thanks

 

I have ordered a new sensor, just have to wait 2 weeks for delivery now. Can still use the car though, the fault is not occuring every time I drive it.

 

Might still be worth checking the wiring / connector condition in the meantime.

 

True, I very much doubt that there will be a problem there as i live in the South of France and corrosion has never been a problem with any of my cars here.

I will check it though.

 

It could be in the sensor itself, or the connector point there, and caused by a seal leak within the sensor. If this was the case, your replacement will fix the issue.

 

Have checked the connector and wiring today and they are both in good condition so I am fairly confident that the new sensor will fix the problem.
Incidently the light has not come on since I ordered the new sensor, Typical!
I will change it anyway though.

 

My car has started doing this again, i've changed the sensor once and the fault went away for some time but now needs doing again, i suspect it's a build up of particles on the 2 probes thats causing the problem, some times cleaning the sensor works...for a while but i'm thinking more regular coolant/antifreeze change would help as this will aid getting rid of all the particles within the cooling system that builds up on the sensor probes. Many years ago i wondered why these sensors were done away with on some cars, i think i know why now.....

 

Still waiting for my new sensor to arrive. But it has only done it once since I ordered the new part.