Fixing Citroen C3 1.4i Petrol False Overheat Warning

In this video I explain the cause a false overheat warning on a 1.4i petrol Citroen C3. This is a problem on some other PSA vehicles fitted with this 73 BHP 8 Valve petrol engine.

[@davepenton4137]

Just an update to my previous post. Having read the Haynes manual and looked at the wiring diagram. The only thing the Blue (1 wire ) ECT does is high temperature. The green (2 wire ) does everything else including the fan and gauge. I've disconnected the Blue and the car now runs as it should. The wire from the Blue sensor is connected into the green sensor ( somewhere ) this then goes to the ECU. So from my experience the Blue, is purely for 120 C overheat. I've had electronic thermostat on engine on both sensors whilst driving the car and both are fine IE around 80 C peak. With the Blue sensor plugged in according to live data it goes from 206 F to 245 F which brings the high temp light on. So I'm now driving around with Blue not connected. What is the probable cause is that somewhere the wire from the blue sensor is shorting out. But unplugged that won't occur. Hope this helps others.

[@seabubbleuk]

Thanks very much John. Just what I needed as my Daughters car is getting this issue.

[@richardkeur6150]

Thanks for the tip, C3 1.4 from 2004, same problem 👍

[@brasil33]

Excellent explanation! Thank you for this!

[@Wildonetwo3]

Spot on. We have a C3 999cc and we've been messing about looking at OBD error codes etc with no look (even mechanics!) This base model C3 has not gage just a blue temp light for cold and when off normal, however an engine warning comes on occasionally with can full on even when it's cold (as you describe a while back when you made this vid). So..... Thank you for doing this research and keeping this vid up there. Have a beer on me 😊.

[@emelkaragoz1161]

i have citroen c3 temp gauge problem. 2015 model. They can't find the reason. I can't fix it. What do you recommend

[@benstart2936]

Great clear video, mine has the same symptoms

[@thunderpants]

Useful thanks! I might have the same issue on a 2017 Dispatch

[@Ramon0489]

Thank you very much. You helped me a lot!

[@p7_a757]

Thanks very helpful

[@mrgrumpy5116]

thanks for sharing ..

[@gabrielnuckowski9623]

So this blue thing must be change?

[@ramimh2841]

Hello John.. My car is a 2003 Citroen C3 and I have the same problem, but I do not have the blue temperature sensor.... The temperature rises from 3 to 5 and the cooling fan does not work..... Do you have a solution? .... Thank you

[@LeMasterYT]

Hi, i have the Same Problem and can't find something helpfull online. So, do you have an sollution found?

[@djcurtneswithyou1329]

Thanks very helpful 👍🏽👍🏽

[@antoonsorg]

I have the same problem with an C3 2002 1.4 16V can I just disconnect the plug and then drive safely home to fix the sensor.

[@tanklesssubset3815]

My car's radiator fan doesn't kick in and it does work when i turn on the aircon. I plug and unplug the grey plug on top of the radiator, sometimes it kicks in and the temperature gauge does down to 3 bars and then the fan stops and bars go up to 6. Is the solution in the video gonna fix my problem as well?

[@davepenton4137]

Hi I have this problem, car runs fine, then temp goes to 5 then drops. After a few times of this happening, engine management light came on. Read the codes and it said Po117 & Po118. Changed both sensors and thermostat. Road tested and still doing the same. Difference now is the temperature gauge doesn’t drop until car has cooled sufficiently after turning engine off. Yesterday after having the car running on my drive, for 45 minutes, I then took it for a drive after 4 mile went to high temp bar 5 turned off, then drove a mile it went up, stopped repeated, drove home 4 mile and left engine running for 45 minutes all was fine. Any ideas as to what it could be now? Just to update, I changed blue sensor a week ago, code then changed to Po117. Changed the green one yesterday. Brings us up to date.

[@L0SHKE]

I have the same problem on C2, changed both sensors and the issue is still there.

[@goldenultra]

If the issue is still there, then maybe the engine is over heating. You can check other things like pcv valve or coolant change? There is a coolant test that can be done with an amp meter. There is also a phone app called torque pro that check for engine errors that works with a Bluetooth obd.

[@L0SHKE]

@@goldenultra Thanks!

[@takemoremaphosa3111]

Mine is also doing the same especially when l am in traffic .what should l do.havent changed any sensor yet.l really need your help.thank you.

[@judedunlop5295]

Thanks for sharing 🙂

[@Phae576]

If this is broken on mine. Could it be responsible for not starting the engine cooling fan? Checked all relay&fuses and they seem to be just fine.

[@jarnokarlsson1867]

There is morelikely fan resistor, that could be broken

[@samsaka9225]

Thank you so much

[@tasos209]

changed both sensors. but keeps showing full temp only when the fan turns on. when the fan turns off goes back to 3 bars instant. ??? no clue any advice?

[@JedBlake-ev9mn]

Same on mine. Did you find out what it was?

[@Nphillips42]

My car is doing this now Also it’s loosing the coolant from the coolant tank ! I can drive home after the lights going on for the temperature and then in the morning the coolant tank is empty !! Please help 😊

[@johnnodge4327]

If it's loosing coolant, there's something wrong with the cooling system. The issue described here is just a sensor fault, not a cooling system fault. No don't drive it without coolant.

[@msjdna]

Hello ... Is this sensor has role in switching fan ... As my first speed fan was at 90 now kick at 97 .

[@gokhans.3856]

does C2 Vtr has also mentioned 2 sensors or just have only one. Do you have any idea? Because i am experiencing same problem.

[@johnnodge4327]

It might well do. I'm not up on the VTR engine, just the 8 valve 1.4. It's easy to check to see if you have the the overheat sensor though. ;-)

[@L0SHKE]

I know it was 3 years ago, but i have the same problem on my C2 VTR, did you manage to fix it?

[@noednest7100]

Hello, my c3 does the exact same thing after I drive a while it Will show the maximum red, but when I turn off the car it sounds like the car is still on and if you go to the front you Will hear a loud noise like its not turned off? I would appreciate if you could answer me :)

[@johnnodge4327]

It's probably the cooling fan still on, as the ECM thinks the engine is overheating.

[@sushichefs]

Do you have any message like motor failure or engine signs in dashboard?

[@kyrpousin]

It's the ventilateur trying to "cool" the engine but the engine isn't even heated

[@chriz74]

what year is your car ? I have the same symptom on 2002 C3 FC_ 1.4i. I ordered the sensor that you suggested. I disassembled the air filter housing and to my surprise there is no sensor down there. There's the hole where it should be but no sensor nor electric cable.

[@johnnodge4327]

It was a 2002 1.4 8 valve.

[@chriz74]

@@johnnodge4327 same car but no sensor here.

[@LeMasterYT]

Some Sollution?

[@chriz74]

@@LeMasterYT it was the thermostat

[@haroonmet]

Hello John, thanks for the share.... Mine is Citroen C3 1.4 petrol as well. It is also showing me overheating warning but strangely it shoots from 3 bar to the maximum without going to the 4th or 5th. Any suggestions from your side? My mechanic tested it completely by the recommended techniques and he says there is no fault in the system. We changed the liquid completely and I drove for 2300 km (around 1400 miles) and it is now starting to show the same problem. What is your take on such case?

[@johnnodge4327]

That is what my daughters C3 was doing. I replace the sensor shown in this video to cure that issue.

[@haroonmet]

@@johnnodge4327 Thank you for the reply. Let me update you with my recent experience. My mechanic also had suggested previously that the fan was not switching on sometimes, hence some sort of memory issue exists in the car's computer? It was reset before the drive of 2300 km. Now today again I saw the overheat problem. I tried to diagnose myself and it became true what the mechanic said, the fan did not switch on even the overheating warning came on the dash. I did not drive the car for a long distance, just a routine city drive it was. The car wasn't as such in an overheated situation. Incredibly, the air conditioning did not switch on afterwards, it was working before. Definitely it could be an electronic problem. Next week I'll go to the mechanic for the subsequent repair/reset of the computer and also will get the sensors changed/refreshed. Thank you once again.

[@brucemiller5343]

This happens to my 1.4 hdi but it only shows overheat for like 2 seconds ive tried catching my fan working but not yet

[@jw200]

Coolant will leak after I remove sensor? Or coolant is way below the sensor with cold engine?

[@sar2908]

You will need to partially drain the cooling system before unscrewing the sensor.

[@ilijapoleksic9493]

Thx....👍

[@GromDarkwater]

I have this issue, how much would a mechanic charge to have this done and what parts do I need to buy

[@johnnodge4327]

It took me less than 30 minutes to change the high temperature sensor, and a litre of coolant to top up what was lost while changing the sensor. How much it costs is between you and your mechanic, or you could do it yourself.

[@GromDarkwater]

@@johnnodge4327 to do it myself what parts/tools will I need

[@johnnodge4327]

You need the sensor and some coolant, and some tools to remove various components to get to the sensor. I think the sensor needs a 19mm socket to remove it, but I can't remember, as I did this job on someone else's car a couple a years ago.

[@ophirburton]

@@johnnodge4327 thanks for the video. Any guides for novices like myself on how to do it myself? Not 100% confident on guessing

[@BrunoBrozovic]

Hi! This video is awesome! I have a problem that only when I drive downhill for a few kilometers, I get Engine temp too high warning, and the red light is lit on the dashboard. My Citroen C3 is 2006., 1.4 petrol engine and I don't have any gauge for coolant temperature tracking, only red light when the temperature is too high. Also, my car doesn't have a blue sensor at all, only green. I changed the green sensor, and it's still the same-the warning light is up when I go downhill for a few kilometers. When this happened, I shut down the engine and went to check-the engine is not overheated, the coolant level is okay, and there is no leakage anywhere. I doubt my thermostat is failing so I try to change that also. Maybe someone has some other advice?

[@dirklerxstprof2112]

My son has one of these cars with the same problem, i replaced both sensors, still got the same problem, what was odd to me was that the sensor on the end of the block ( blue one ) screws into a dry blank hole in the end of the cylinder head, i can only assume it is reading the temperature of the cylinder head itself and not the circulating coolant, very strange. i'm beginning to think it's a wiring problem.

[@davepenton4137]

Did you ever resolve the issue? I’ve changed both my sensors and still got same issue.

[@jarnokarlsson1867]

@@davepenton4137check and clear all earth points

[@FordTransitvan]

Thank you

[@barrybakewell7968]

hi just come across your video I have c3 citreon and my temperature goes up to 3 bars and stays their is this normal or is it something else thanks barry

[@sar2908]

Hi, 3 bars is normal 👍

[@tihomirvicentijevic2519]

Tnx bro!

[@fahmyshaker307]

What the name of the part so I can buy?

[@bjorn5665]

024286

[@raymoises9729]

Hi m8 would you knw any thing about Citroen c3 1.4 petrol anti pollution fault, I have change a both 02 sensor, knock sensor, purge valve, new spark plugs. I am pulling my hair

[@raymoises9729]

Pls help have u got wire diagram c3?

[@JJSmith1100]

Ever got is sorted?

[@raymoises9729]

Johan Smith Indeed I finally got it fix. I find out in the ECU brown socket two pin was missing. I opened the ECU box and connected directly wire into the plugs, engine management light gone and anti pollution warning gone two

[@chriz74]

Do you know the part name / number ?

[@johnnodge4327]

Temperature Sensor 024286 was the part I used.

[@chriz74]

John Nodge thanks

[@chriz74]

John Nodge however in the car my gf has the alert comes in but the fan doesn’t start

[@haroonmet]

@@chriz74 this happened to me many times recently. Check if there is the computer command issue in the car.

[@chriz74]

Haroon Mahmood computer command issue ?

[@yaakoubbelamri6225]

J'ai une c3 essence depuis peu il y a une perte de puissance considérable vous pouvez m'aidez svp?

[@djcurtneswithyou1329]

Bjr j’espère que vous avez pu trouver la solution pour votre perte de puissance sinon tout dépend j’ai déjà un problème similaire auparavant j’ai du changé de Throttle body ou vérifie votre Map sensor ( capteur map)

[@anthonygill8541]

J’ai eu le même problème y avait un problème de thermostat. Ça disait Engine fault sur le tableau de bord. Problème moteur quoi. J’ai payé 300 euros pour reparer ça. Je dépassais pas les 30kms. 1.2l de 2012

[@MatthewGanley]

Had this problem last year fix it year later having same problem brought new sensor still playing up so my friend look my he said water pump causing my car to overheat

[@pokerbmx1]

I had the same problem on a Peugeot 206 1.4 petrol 2002 model... it was the slow cooling fan relay, cos there is the fast fan relay and the slow one.. but after 2/3 years i have the same problem and didint work for me this time ... so ithink i need to try this out

[@mrgrumpy5116]

hi .. are the fan relays under the dash, I think my 206 has a fan relay problem.

[@pokerbmx1]

@@mrgrumpy5116 kzbin.info/www/bejne/a4CpmmaIo5alobs 2.20min the one on top is the slow speed relay and the one under is the fast speed relay

[@pokerbmx1]

Check the cables for corrosion this time my problem it was the corrosion...

[@mrgrumpy5116]

now I remember .. thanks a lot for the call ..and the link

[@pokerbmx1]

@@mrgrumpy5116 you're welcome I hope you will fix the problem :)

[@andywebber8749]

I have just had to change the thermostat + housing on my c3 2007 14i 5 door, as it was cracked. with this off I looked for this connect on the side of the block, this car dont have one is that normal. all that was there was a shiney hole in the block, no Blue sensor fiited ?.

[@sampledger1023]

That’s a sensor

[@delsonluizgonzaga6063]

Boa noite

[@SmallJabu]

Ooi pl.l Kim

[@satbilla9291]

Hi what happens if this is unplugged when engine running will the fan kick in? My Peugeot 206 is same engine and fan does not work old one was seized so I replaced it with new one it still doesn’t work when car is hot. Any advice???

[@mike311271]

very helpful thank you