Hello, I can't find any solution online for this problem. This car sometimes displays an overheat alarm and the engine radiator fan doesn't start.
I checked with obd 2.. the alarm appears at 97°. Fan doesn't start. So I put a new fan, same problem, it worked after installation and after two days fault occured again.
Does anyone have any idea?
Radiator fan doesn't start randomly. New fan didn't solve.
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Petrol engine related faults, like injectors, error codes, overheating.
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One question per topic.
Petrol engine related faults, like injectors, error codes, overheating.
You can post more topics if necessary, but only one question per topic.
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My Name: chriz74
- Posts: 13
- Joined: Wed Aug 19, 2020 1:49 pm
- Model: C3 2002-2005, Original shape model
- Year: 2002 (02)
- Engine Size: 1.4 i
- Fuel Type: Petrol
- Mileage: 80000
- Gearbox: Manual 5 speed
- DPF: No
- LHD or RHD: LHD (Europe)
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My Name: C3CAR
- Posts: 2807
- Joined: Wed May 04, 2011 10:01 am
- Model: C3 2002-2005, Original shape model
- Year: 2002 (02)
- Engine Size: 1.4 (16v)
- Fuel Type: Diesel
- Mileage: 140000
- Gearbox: Manual 5 speed
- DPF: No
- LHD or RHD: RHD (UK)
- Engine name: DV4 16-valve diesel (90 PS)
- Has thanked: 217 times
- Been thanked: 109 times
Is yours the engine with two temperature sensors? Worth checking. It may be easier to just have a look on the engine.
One sensor is for the warning (which is working) and the other is for the engine ECU that triggers the fan (that sensor is probably faulty).
One sensor is for the warning (which is working) and the other is for the engine ECU that triggers the fan (that sensor is probably faulty).
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My Name: chriz74
- Posts: 13
- Joined: Wed Aug 19, 2020 1:49 pm
- Model: C3 2002-2005, Original shape model
- Year: 2002 (02)
- Engine Size: 1.4 i
- Fuel Type: Petrol
- Mileage: 80000
- Gearbox: Manual 5 speed
- DPF: No
- LHD or RHD: LHD (Europe)
Only one sensor. I know because I ordered that blue one only to find that it was not present at all.
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My Name: C3CAR
- Posts: 2807
- Joined: Wed May 04, 2011 10:01 am
- Model: C3 2002-2005, Original shape model
- Year: 2002 (02)
- Engine Size: 1.4 (16v)
- Fuel Type: Diesel
- Mileage: 140000
- Gearbox: Manual 5 speed
- DPF: No
- LHD or RHD: RHD (UK)
- Engine name: DV4 16-valve diesel (90 PS)
- Has thanked: 217 times
- Been thanked: 109 times
-
My Name: Ozvtr
- Posts: 1249
- Joined: Wed Jul 10, 2019 3:31 am
- Model: C3 2002-2005, Original shape model
- Year: 2003 (53)
- Engine Size: 1.4 (8v)
- Fuel Type: Petrol
- Mileage: 80000
- Gearbox: Automatic PRND
- DPF: No
- LHD or RHD: RHD
- Engine name: TU3 (75 PS)
- Location: Brisbane, Australia.
- Has thanked: 63 times
- Been thanked: 373 times
There are 2 sensors (pre 2009?)
1) Green sensor on the top of the thermostat housing. This sensor is used by the engine ECU to monitor the engine coolant outlet temperature. This is used by the ECU for engine management and (if applicable) indicate the temperature on the dash.
2) Blue sensor on the cylinder head behind the air filter mounting bracket and underneath the thermostat housing. This is the "coolant level sensor". I put it in quotes because it doesn't directly monitor the level of the coolant. But if there is no coolant in the cylinder head the head will get hot and trip this sensor.
The two sensors are in series. The blue sensor provides the earth for the green sensor. If the green sensor goes open circuit or the connector is removed or the blue sensor "trips" either the temp gauge will show all the bars or the over temp light will come on (depending on your car model). The blue sensor goes open circuit when the head reaches 120'C.
So, if you are getting random over temp warnings either one or both of the sensors are faulty, the green connector is loose, the blue connector is loose, there is a wiring fault between the green sensor and the engine ECU or the coolant level is low.
If the over temp warning comes on, the engine fan should run.
1) Green sensor on the top of the thermostat housing. This sensor is used by the engine ECU to monitor the engine coolant outlet temperature. This is used by the ECU for engine management and (if applicable) indicate the temperature on the dash.
2) Blue sensor on the cylinder head behind the air filter mounting bracket and underneath the thermostat housing. This is the "coolant level sensor". I put it in quotes because it doesn't directly monitor the level of the coolant. But if there is no coolant in the cylinder head the head will get hot and trip this sensor.
The two sensors are in series. The blue sensor provides the earth for the green sensor. If the green sensor goes open circuit or the connector is removed or the blue sensor "trips" either the temp gauge will show all the bars or the over temp light will come on (depending on your car model). The blue sensor goes open circuit when the head reaches 120'C.
So, if you are getting random over temp warnings either one or both of the sensors are faulty, the green connector is loose, the blue connector is loose, there is a wiring fault between the green sensor and the engine ECU or the coolant level is low.
If the over temp warning comes on, the engine fan should run.
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My Name: chriz74
- Posts: 13
- Joined: Wed Aug 19, 2020 1:49 pm
- Model: C3 2002-2005, Original shape model
- Year: 2002 (02)
- Engine Size: 1.4 i
- Fuel Type: Petrol
- Mileage: 80000
- Gearbox: Manual 5 speed
- DPF: No
- LHD or RHD: LHD (Europe)
-
My Name: chriz74
- Posts: 13
- Joined: Wed Aug 19, 2020 1:49 pm
- Model: C3 2002-2005, Original shape model
- Year: 2002 (02)
- Engine Size: 1.4 i
- Fuel Type: Petrol
- Mileage: 80000
- Gearbox: Manual 5 speed
- DPF: No
- LHD or RHD: LHD (Europe)
No, there is only one sensor, the green one. Alarm appears at 97C , it can’t be a faulty sensor because it’s reading the temperature correctly. At 97C fan should start but it doesn’t. Sometimes it starts, others doesn’t.Ozvtr wrote: ↑Thu Aug 20, 2020 10:14 pm There are 2 sensors (pre 2009?)
1) Green sensor on the top of the thermostat housing. This sensor is used by the engine ECU to monitor the engine coolant outlet temperature. This is used by the ECU for engine management and (if applicable) indicate the temperature on the dash.
2) Blue sensor on the cylinder head behind the air filter mounting bracket and underneath the thermostat housing. This is the "coolant level sensor". I put it in quotes because it doesn't directly monitor the level of the coolant. But if there is no coolant in the cylinder head the head will get hot and trip this sensor.
The two sensors are in series. The blue sensor provides the earth for the green sensor. If the green sensor goes open circuit or the connector is removed or the blue sensor "trips" either the temp gauge will show all the bars or the over temp light will come on (depending on your car model). The blue sensor goes open circuit when the head reaches 120'C.
So, if you are getting random over temp warnings either one or both of the sensors are faulty, the green connector is loose, the blue connector is loose, there is a wiring fault between the green sensor and the engine ECU or the coolant level is low.
If the over temp warning comes on, the engine fan should run.
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My Name: Arfur Dent
- Posts: 3544
- Joined: Sat Jul 23, 2011 3:47 pm
- Model: C3 2002-2005, Original shape model
- Year: 2002 (52)
- Engine Size: 1.4 (16v)
- Fuel Type: Diesel
- Mileage: 100000
- Gearbox: Manual 5 speed
- DPF: No
- LHD or RHD: RHD (UK)
- Engine name: DV4 16-valve diesel (90 PS)
- Has thanked: 355 times
- Been thanked: 139 times
Air conditioning or not?
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-
My Name: chriz74
- Posts: 13
- Joined: Wed Aug 19, 2020 1:49 pm
- Model: C3 2002-2005, Original shape model
- Year: 2002 (02)
- Engine Size: 1.4 i
- Fuel Type: Petrol
- Mileage: 80000
- Gearbox: Manual 5 speed
- DPF: No
- LHD or RHD: LHD (Europe)
-
My Name: Arfur Dent
- Posts: 3544
- Joined: Sat Jul 23, 2011 3:47 pm
- Model: C3 2002-2005, Original shape model
- Year: 2002 (52)
- Engine Size: 1.4 (16v)
- Fuel Type: Diesel
- Mileage: 100000
- Gearbox: Manual 5 speed
- DPF: No
- LHD or RHD: RHD (UK)
- Engine name: DV4 16-valve diesel (90 PS)
- Has thanked: 355 times
- Been thanked: 139 times
Thanks,
There are 2 diagrams for the cooling fan control for the KFV/TU3 engine that I have access to.
The one without A/C has a relay, but the one with A/C is more complicated with some solid state device.
I also found the diagrams of the locations for the 2 engine coolant sensors on the TU3/KFV for early cars.
I am going to add them here just because I am sure google will direct people here looking for engine coolant sensors on the C3
- Engine temperature sensor Citroen C3
- Engine temperature sensor Citroen C3
I will dig out the fan motor electrical diagram
You can add an avatar to your account - Avatar or change your vehicle details - Car Bio or even add a signature to your posts - Signature. But this is not all you can do in the User Control Panel
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