C3 Radiator Fan Comes On Quite Often.

[drakes]

I first posted this problem in September in the Citroen Xsara Picasso forum as I have been a member there for a few years and couldn't seem to be able to post here.   Unfortunately I have had no commenta at all, possibly due to it being in the wrong forum.  Anyhow, I've registered for the C3 forum as well now so here goes. 

 

I have, from new,  a C3 Desire 07 plate, 1.4 petrol, 60000 mls and regularly serviced by main dealer.  My radiator fan very rarely comes on except occasionally when I'm in traffic congestion on a hot day.  However, for the last few weeks it has been coming on quite often but more when I am moving rather than when stationary in a jam.  Some times, for instance, I can hear it when approaching a traffic island but it turns off as I slow down.  This is also an intermittent thing as some days it doesn't come on at all.  My journeys are often no more than 20 miles and I get no warning of any kind that the engine may be overheating.  There is no temperature gauge on the dash on this model.  Coolant level in expansion tank is ok but I do sometimes have to top it up from min to max every 2 or 3 months (have been doing this for a few years now).  I'm wondering if it could be a fault with the temperature sensor and/or thermostat and if so how easy is it to change them and any guidance as to where they are under the bonnet would help.  Any advice would be welcome.

 

Thanks

 

Drakes

 

 

[Johndouglas]

Hello & welcome to the forum. Can't help you with your problem but my fellow moderator Paul has a C3 in his family fleet. Unfortunately he's away right now but will be back in a few days.

[drakes]

Hi, thanks for the message, I'll wait in hope that he will have some suggestions.

 

Dave

[paul.h]

What power output is the engine ? The radiator fan will always come on if the air con is being used so something to check. If the air con is not being used then you should use a code reader that gives live data to see what temperature the sensor is giving and helping to decide if it is giving expected values (eg about 10°C before starting the car first time of the day, about 90°C when the thermostat opens). Typically the fan will cut in at 96°C and then cut out when 2°C lower. The fan may be a 2 speed one with the higher speed if the temp continues to rise. On the 1.4 petrol engine there are 2 temp sensors, one for the gauge on top of the cylinder head and one to give warning of a high temp on the side of the cylinder head.

 

You can also make sure the radiator is not blocked and that the thermostat is opening before the fan starts (keep hands, etc out of the way) without using a code reader.

 

Having to top up the coolant at your frequency is not normal, you need to look for any leaks and check the coolant tank cap is on good condition (an O ring on it seals against the inside of the tank neck).

[drakes]

Hi paul.h, many thanks for your reply.  Not sure what the power output is (where would I find out?) apart from it being 1.4 petrol engine.  Fan comes on when a/c is not being used, generally for a short time and then turns off, but it can stay on for several minutes, even when moving at 40mph+ for a few miles.  Yesterday I did a fair bit of running around to shops and stuff, stopping/starting here and there, probably covering 20 miles in all including 10 minutes in very slow moving traffic and fan never came on.  Went out later in afternoon for there and back journey of 15 mls and fan came on a couple of times.   Unfortunately, I do not have a code reader so may have to try the manual method.  Initially I was thinking of fitting new coolant temp sensor  and if problem persists, a new thermostat etc.  I need to get a Haynes manual I think.  I've been topping up the coolant periodically for several years but never found a leak.  Liquid in expansion tank does not have a scummy film that might indicate head casket problems.  I will replace expansion tank cap for new one.

 

Thanks for your advice.

 

Dave

[paul.h]

If you decide to get a code reader this one from Gendan is a decent price at £38.95 and gives some live data https://www.gendan.co.uk/product_FXNT200.html

The 16 pin EOBD socket is in the glove box at the left side behind a cover that needs pulling off.

 

The tank cap from a Citroen dealer is about £3 so it is not worthwhile going anywhere else for one.

 

If the engine is the 75 bhp one it has 8 valves and the cam cover at the top of the cylinder head is narrow, if it was a 16 valve engine the cover is wider due to 2 cam shafts. In the VIN the engine type is included and for the 8 valve will have ....KFV.... You can see the VIN at the bottom of the windscreen and on the V5C document and the car Warranty and Maintenance book.

[drakes]

Ok Paul, many thanks for the advice and information.

 

Dave