General EOBD code!! PO 115

[Brin]

Hi,
Driving car today stuck in stand still and the temp went to half way then my fan kicked in. The road became free and i accelerated from stood still to 70mph to try to cool down the radiator by getting air to it. Straight away my temp went to 1/4...

2 mins later i notice the engine management light has come on and the temp dropped straight to zero on the C mark but the engine was obviously still hot because i was stopped at lights again.

Got diagnostic kit on it and came up with EOBD code PO 115

Checked what code stands for i think it said COOLANT TEMPERATURE SENSOR (the one the screws into the cylinder head i think).

Does anybody know where i can find this COOLANT TEMP SENSOR on the engine and where i cant buy a new one from.

BTW got code cleared and light went out but has just come back on now after driving about 10 mile

Cheers
Brin

 

[fingers99]

What's the car?

 

[Brin]

What's the car?

Punto mk2 2002 active 1.2l 8v

 

[fingers99]

Should be on the extreme right hand (facing backards) of the inlet manifold, towards the head. Usually they're green on the MPI cars. Check the wiring while you're in there as that can trigger a fault, too.

 

[Davren]

I think the coolant temperature sensor on your engine is on the thermostat housing.

Bear in mind that fault code P0115 = Engine Coolant Temperature Circuit Malfunction, so it's not neccessarily the sensor that's faulty, it could be the wiring or connector etc.

Not sure if there's guide to testing the sensor in the Punto guides, but there's one in the Stilo guides here:

https://www.fiatforum.com/stilo-guides/104106-testing-radiator-fan-engine-temp-sensor-circuits.html

Dave.

 

[Brin]

Should be on the extreme right hand (facing backards) of the inlet manifold, towards the head. Usually they're green on the MPI cars. Check the wiring while you're in there as that can trigger a fault, too.

Thanxs m8 il look on the back i was looking around where thermostat housing coolant pipe goes into the cylinder head, behind that on the side there is something screwed into the head but it isnt green and its very close to that pipe has wire going to it. Will that be the sensor or is it on the back of the head as you stated il try taking pic tmoro of what i am talking about it nearly te top but burried in there hard to see or get hands on.

 

[Brin]

I think the coolant temperature sensor on your engine is on the thermostat housing.

Bear in mind that fault code P0115 = Engine Coolant Temperature Circuit Malfunction, so it's not neccessarily the sensor that's faulty, it could be the wiring or connector etc.

Not sure if there's guide to testing the sensor in the Punto guides, but there's one in the Stilo guides here:

https://www.fiatforum.com/stilo-guides/104106-testing-radiator-fan-engine-temp-sensor-circuits.html

Dave.

So should i check that sensor the wires to it and the sensor in the radiator aswel.

 

[Davren]

Having established which sensor is your engine coolant temperature sensor, I would test it at different temperatures according to the guide. No point buying a new sensor if you don't need one.

If your engine has a seperate sensor in the radiator, you would only need to test that if the radiator fan isn't working.

I believe item 2 in this diagram is the engine coolant temperature sensor, but Brin probably knows more about the Punto than I do.

Dave.

 

[fingers99]

That looks like a 16v inlet mani.

Just follow the pipe from the heater back to the head. That should be it. 2 pin connector.

No need, I think, to worry about the fan -- you've established that that works.

 

[Kalev]

Hope this helps..

 

[fingers99]

Very good! And it's green, too!

 

[Brin]

Thank you so much pics help so much, i will try finding it today as its very sunny outside. I have a good idea what it is now and where it is, i will remove it and test it before buying a new one. Il let you know how it goes.

Thanks again everyone for all your help.

BTW if i remove the sensor will the coolant start to flow out of the hole in the head then?

 

[Davren]

Yes... but it won't drain completely. You could put a cork or something in the hole to stop it whilst you have the sensor out.

Dave.

 

[Brin]

Right iv got the COOLANT TEMP SENSOR i got it from euro parts for £3.00 not bad eh. Is the sensor just a small srew in probe with a connector with 2 pins on it?

If so iv got the right thing because they had something for £20 that was the housing or something with a temp sensor on it. It wass a larger piece of plastic mounting with that temp sensor already screwed in.

 

[fingers99]

What you have will do -- Fiat sell pre-assembled bits which pop and screw into the inlet mani -- what you have will do the job.

 

[Brin]

Right now i still havnt done anythiing to try and fix this but thought id just say that the temp gauge goes straight to zero when i know that engine is hot then my engine management light comes on to tell me that i have a fault.

I got the code cleared on diagnostics then on way home light came back on and temp at zero, i expected this because i havnt actually done anything to fix it yet.

Then while driving about an hour the light just decides to go out and the temp gauge starts to work again on its own!

Its happened twice now engine management comes on temp goes to zero drive a bit or leave it over night and the temp is working again and engine management goes off!

What does this mean?

 

[Liquidh2o]

Right now i still havnt done anythiing to try and fix this but thought id just say that the temp gauge goes straight to zero when i know that engine is hot then my engine management light comes on to tell me that i have a fault.

I got the code cleared on diagnostics then on way home light came back on and temp at zero, i expected this because i havnt actually done anything to fix it yet.

Then while driving about an hour the light just decides to go out and the temp gauge starts to work again on its own!

Its happened twice now engine management comes on temp goes to zero drive a bit or leave it over night and the temp is working again and engine management goes off!

What does this mean?

sounds like a bad connection somewhere

 

[Davren]

Right now i still havnt done anythiing to try and fix this but thought id just say that the temp gauge goes straight to zero when i know that engine is hot then my engine management light comes on to tell me that i have a fault.

I got the code cleared on diagnostics then on way home light came back on and temp at zero, i expected this because i havnt actually done anything to fix it yet.

Then while driving about an hour the light just decides to go out and the temp gauge starts to work again on its own!

Its happened twice now engine management comes on temp goes to zero drive a bit or leave it over night and the temp is working again and engine management goes off!

What does this mean?

sounds like a bad connection somewhere

Code P0115 = Engine Coolant Temperature Circuit Malfunction, so it's very likely to be a connector problem as Liquidh2o says. Check the connector on the sensor, you may not need to fit a new sensor.

Dave.

 

[Brin]

Right finaally got round to fitting this new coolant temp sensor.

Quite difficult as FIAT try putting everything at the back of the engine wherre nobodys hands can reach.

I needed the little green sensor but on PUNTOS the sensor doesnt just simply screw out because it is sort of trapped in the housing by plastic stubs you have to remove the whole housing connected to the inlet manifold and replace the whole plastic housing with sensor already fixed in with stubs, cost £20 for the sensor with housing luckily i had bout the littlle green sensor and the one with the housing so i didnt have to go back out for parts.

USed diagotics kit to clear the error code fired engine up and let it idle for a while bled the system, took it for a test drive did coolant pressure test, checked coolant level, reconnect diagonstics to check if error code reappear but it didnt so looks like it has cured the problem.

 

[Brin]

Right now i have a brand new coolant temp sensor for the cylinder head that never came in use does anyone want it £6 including P&P anywhere in the UK??

Iv alsoposted in classifed but no interest yet?