Stuck in France- Urgent help needed with overheating C5

[Philjw]

Hi Guys,
Down on the Dordogne in southern France with the temperature reaching 41C today and the cooling system on the C5 has decided to play up.
It has done this twice in 3 days. The temp guauge shows normal then suddenly goes off the scale and the screen warning for too high engine temp is shown. First time the temp dropped back to normal after a few seconds. Today I stopped and it was 15 minutes for the indicated temp to return to normal. The fan does not appear to be running correctly but most of the time there is no issue. Today whilst the guage was off the scale the outer blade of the fan was runing for a couple of seconds at a time, the inner blade did not move and would not turn when poked with a stick.
Fans don't run when the air con is on either and this too has been misbehaving - yesterday it was blowing hot not cold air
What do we think is happening here? Is it a sensor or the fan itself that is out of order? On older models it was possible to remove one of the connectors from the bitron unit to make the fans run at full speed. Is there something similar I could try with the C5. If so exactly where do I findthe connector? I have hardly any tools in the car - it's never let me down on a holiday trip before. I do have a multimeter with me. I'm due to come home on Sunday.
Does this sound like an issue that a dealer could diagnose easily i.e. would there be stored fault codes? I don't relish the prospect of explaining the problem in my basic French. Tomorrow is the only day I could take the car to a dealer.
To me it feels like the problem is with the fan itself - the car has nearly 132K miles on the clock - but since it is fine most of the time how does that work with a duff fan?
Please let me have your thoughts - It's a long way home.
Thanks

Phil

[C5Alan]

if you can run a wire straight from the batt to the fan this would check it they are working or not and could be left connected all the time except when parked or fit a switch to turn on and off this should work to get you home im sure you could get some wire and bits in one of the big supermarkets

[davoxx]

Thermostat is dead is a possibility, it gets hot, but the fan does not kick in. See a dealer as it is cheaper than a blown head gasket.

[VertVega]

... The temp guauge shows normal then suddenly goes off the scale and the screen warning for too high engine temp is shown. ...

I had similar case with my Xantia many years ago. Problem was caused because of battery earth cable was full with dander like stuff. So check earth terminal and also the other end of the cable where it should go somewhere on top of the gearbox.
Cleaning would help.

... Fans don't run when the air con is on either and this too has been misbehaving - yesterday it was blowing hot not cold air What do we think is happening here?...

This seems to be caused by the dying/dead radiator fan motor.
When air condition is on they must be running. Do you have 2 fans like in Xantia?
The fans get power in a different way at low speed and high speed (current flow in parallel and series).

With the engine off try to spin them separately by hand. The one spinning for longer time is the one causing the problem.

[old'uns]

had same with my 02 few yrs ago...temp rising,beeps galore etc
took to local garage Ile de Re, pigeon French to explain temp gauge going up, fans not on..new rad, stat etc, driving home hot day, same things.
never had problem for 3 yrs, not hot enough!
decide to sort out Air-con slowly getting warmer, re-gas, still same.
find out fan also helps air-con, bumper off...guess what? yup...fan seized, probably original cause all those years ago.

i'd lay odds same thing with yours

[Lighty]

You cant just run a wire to the fan on an 05 plate C5, assuming that is what you are running, this will cause more problems than you need at the moment.
The fan unit has an ecu built into it, so is quite technical. The fan runs at various speeds depending on what it is told , and is almost infinitely variable , rather than just fast and slow.
You need to determine if the car is really overheating, or just saying so on the gauge.
If the fan will not turn with your stick, then it is probably seized, and you are stuffed. I think you will end up seeking help at a French garage. in the UK, a fan and ecu assembly is well over £250 from memory.
Sorry

Dealer can actuate the fan with the Lexia, so relatively easy to diagnose.

[Rhothgar]

Quick fix to get moving is to remove radiator cap, top up if low and drive. No pressure generally equals no loss. It saved my bacon on a car which had haemorraged 2 litres of water in 6 miles on my way into Stafford once. I still had a 56 mile drive back to Nottingham. Cap off - sorted!

[Philjw]

Thanks for all your replies. We got home safely with no further issues. Had the car looked at by a local indie Cit specialist today. No fault codes stored. Try as they might they could not get the fans to run and thought it likely the issue is the fan itself as we feared. I'll see what the weather is like at the weekend and strip out the fan to see if it is seized. If it looks possible to dismantle or otherwise free it up I'll give it a go. I'm not hopeful though. Looks like I'll be shelling out for a new one.

[old'uns]

pretty sure i had price from dealer for fan..not too far from £300?
politely said no as didn't want to double value of car

got one from ECP around £140 'ish, had to slightly alter wiring as the connectors didn't match but no great problem