OP
OP
Thanks. I take it you mean the radiator inlet pipe? The frontmost pipe coming off the thermostat?
Cheers!
General the Mystery of Code P1481
- Thread starter Greggers
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General the Mystery of Code P1481
Thanks. I take it you mean the radiator inlet pipe? The frontmost pipe coming off the thermostat?
Cheers!
Yes I think so, the pipe leading out from your thermostat
OP
OP
Cool. I've just been trying to get my head around the cooling recirculation drawings... I think I've got it now
So, it looks like I've got three possible issues now following on from the Selespeed repair... Why do I feel like I bought a dog?
At least the car runs really well and I've got a comprehensive warranty 1) Stuck Thermostat - check inlet pipe to radiator for sudden heat increase as thermostat opens. If gentle increase in temp, replace thermostat.
2) Fan Control (No fan rotation when a/c switched on, not known about high engine temps yet as thermostat possibly stuck open) - check fuses, cabling, ecu and direct feed volts to fan motor to test. If brave, try Deckchair5's temp sensor test.
3) Noisy Squeeking Compressor (bearing or something else?...) - Hmmm. Don't know...
God, I can't wait to get this car running exactly how I want it...
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What do you guys reckon is the best way to test the radiator fan directly?
Can I just connect the positive and negative terminals of the battery directly to the fan terminals, or will that damage the fan motor?
Can I just connect the positive and negative terminals of the battery directly to the fan terminals, or will that damage the fan motor?
Can I just connect the positive and negative terminals of the battery directly to the fan terminals, or will that damage the fan motor?
It's a good way to lose your fingers if you're not careful
Make sure you disconnect the fan connector and isolate it from the system before you put power directly to the fan and you should be ok electrics wise but be careful with your fingers and any loose clothing like that Roman toga
It's a good way to lose your fingers if you're not careful
Make sure you disconnect the fan connector and isolate it from the system before you put power directly to the fan and you should be ok electrics wise but be careful with your fingers and any loose clothing like that Roman toga
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Roger, roger.
Fingers... check!
Tie... check!
Testicles... check!
Fingers... check!
Tie... check!
Testicles... check!
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LOL, i'll be watching this thread with interest as i have some similar issues but have never led to anything. I replacing my fan ECU unit last year as my rad fan didn't come on at all and aircon was duff. Had numerous testing sessions thanks to Decks
greggers have a search for thread i started about aircon, there is massis of info on there
That sorted the aircon side which is still fine but ever since (or maybe coincidence) my temp gauge has done the same thing as yours Greggers gets to half way quiet quickly but goes from half way down to about 1/3 randomly during a journey of 40ish miles. As yours mine tends to cool down on motorway to.
I tried decks test thingey and was sort of succesful, but found it fiddly worth a go though. the fan kicked in but only at one speed but i also got the temp sensor error
greggers have a search for thread i started about aircon, there is massis of info on there
That sorted the aircon side which is still fine but ever since (or maybe coincidence) my temp gauge has done the same thing as yours Greggers gets to half way quiet quickly but goes from half way down to about 1/3 randomly during a journey of 40ish miles. As yours mine tends to cool down on motorway to.
I tried decks test thingey and was sort of succesful, but found it fiddly worth a go though. the fan kicked in but only at one speed but i also got the temp sensor error
LMFAORoger, roger.
Fingers... check!
Tie... check!
Testicles... check!
OP
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Well, I did the test for the thermostat and unfortunately... it wasn't really definitive
I started the car up and let it warm up on tick-over - the inlet to the rad from the thermostat started cold and warmed up a little bit and slowly (most likely radiant heat from the cylinder block and exhaust manifold?), it then seemed to warm up considerably reasonably quickly (roughly wen the guage had hit 1/3). This made me think that the thermostat is working fine but I'm wondering... should the rad inlet have warmed up at all before the thermostat opened? Maybe the thermostat is operating but not quite as it should, eg. partially opening early ad then fully opening as it warms up? Hmmm... I think I mght repeat the test a couple more times to get a better idea of what's happening.
I've also gone and made up the potentiometer rig that Deckchair5 suggested ready to test my radiator fan. There's a fair bit that needs to be investigated and in an organised logical way... so I think I might put this off until the weekend when I've got the time... plus I'm on the lash for the next two nights
I've got to go to my Fiat dealer on Saturday to get a key coded for the car... contemplating asking them to have a look at both the thermostat and the fan. What do you think? It'll be convenient but I want to put my car through John Whalley rather than Fiat as they really know their Italian cars. Plus, the thought of being without it for any period of time after just having got it back isn't appealling
I started the car up and let it warm up on tick-over - the inlet to the rad from the thermostat started cold and warmed up a little bit and slowly (most likely radiant heat from the cylinder block and exhaust manifold?), it then seemed to warm up considerably reasonably quickly (roughly wen the guage had hit 1/3). This made me think that the thermostat is working fine but I'm wondering... should the rad inlet have warmed up at all before the thermostat opened? Maybe the thermostat is operating but not quite as it should, eg. partially opening early ad then fully opening as it warms up? Hmmm... I think I mght repeat the test a couple more times to get a better idea of what's happening.
I've also gone and made up the potentiometer rig that Deckchair5 suggested ready to test my radiator fan. There's a fair bit that needs to be investigated and in an organised logical way... so I think I might put this off until the weekend when I've got the time... plus I'm on the lash for the next two nights
I've got to go to my Fiat dealer on Saturday to get a key coded for the car... contemplating asking them to have a look at both the thermostat and the fan. What do you think? It'll be convenient but I want to put my car through John Whalley rather than Fiat as they really know their Italian cars. Plus, the thought of being without it for any period of time after just having got it back isn't appealling
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Hmmm.... I've just done Deckchair5's proceedure for faking engine temperature and all went well doing the test on MAR. Firstly, I connected the potentiometer to pins 1 & 2 and then realised that this didn't do anything, so I moved it to pins 1 & 3 and tried that. Temp guage went round as I adjusted the potentiometer... lurvly!
When I went to do the test with the engine running, as soon as I started the engine, I got an engine control warning. I reconnected the thermostat sensor but the alarm still hasn't cleared up. I've restarted the engine a few times, disconnected the battery for 10mins and it's still there
Is this to be expected when doing this test? What could I have done wrong and could I have damaged anything? The engine seems to be running fine when I've had it ticking over/revving on the drive but I'm nervous to take it out on a run anywhere...
Help!
When I went to do the test with the engine running, as soon as I started the engine, I got an engine control warning
. I reconnected the thermostat sensor but the alarm still hasn't cleared up. I've restarted the engine a few times, disconnected the battery for 10mins and it's still there Is this to be expected when doing this test? What could I have done wrong and could I have damaged anything? The engine seems to be running fine when I've had it ticking over/revving on the drive but I'm nervous to take it out on a run anywhere...
Help!
OP
OP
Don't panic! It turns out that the car just recognised that something wasn't right (sensor has three pins and potentiometer only has two). It realises that one of the pins isn't connected and throws it up as an engine fault. It's taken about 5 restarts to clear the issue with a bit of engine running as well.
Decks, can you confirm that it should be pin 1 & 3 for the test and that an engine fault message is what you experienced?
Cheers!
Greggers
Decks, can you confirm that it should be pin 1 & 3 for the test and that an engine fault message is what you experienced?
Cheers!
Greggers
Now be careful oh impetuous one, don't just jab things in wildly
Your eng temp sensor should have just 2 wires going in so those are the pins you connect to. B1 and B2
Your thermostat test has proven your thermostat is opening and not just stuck open which is good .......but it could still be causing problems if it's sloppy and allowing your engine to run too cool. More tests later. Is the pipe finally too hot to keep your hand on?
You need to follow the guide and pre set the resistor to the right sort of values for your engine to feel happy at start up. Choose a resistance which roughly matches your present engine temp then your ecu won't notice a problem and get in a tizz
Did you check if your rad fan came on with engine running and artifically fooling it was getting to high temps with your resistor?
Yes, if you take it beyond its accepted extremes of resistance (see the chart in the Stilo Guides) it will throw up an engine fault but when you reconnect everything and do a few starts it will be happy again
Of course, with your engine running and no cabin air heat selected, your engine should get hotter and hotter until the rad fan kicks in. But that's a bit scary if you suspect your rad fan isn't working at all, and that's where simulating it is at a high engine temperature is safer
Your eng temp sensor should have just 2 wires going in so those are the pins you connect to. B1 and B2
Your thermostat test has proven your thermostat is opening and not just stuck open which is good .......but it could still be causing problems if it's sloppy and allowing your engine to run too cool. More tests later. Is the pipe finally too hot to keep your hand on?
You need to follow the guide and pre set the resistor to the right sort of values for your engine to feel happy at start up. Choose a resistance which roughly matches your present engine temp then your ecu won't notice a problem and get in a tizz
Did you check if your rad fan came on with engine running and artifically fooling it was getting to high temps with your resistor?
Yes, if you take it beyond its accepted extremes of resistance (see the chart in the Stilo Guides) it will throw up an engine fault but when you reconnect everything and do a few starts it will be happy again
Of course, with your engine running and no cabin air heat selected, your engine should get hotter and hotter until the rad fan kicks in. But that's a bit scary if you suspect your rad fan isn't working at all, and that's where simulating it is at a high engine temperature is safer
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Ha ha! I didn't, honestly... unfortunately on the Abarth, you can't see the pins on the sensor as it's blocked by loads of pipes etc On the connector for the sensor though, there are three wires, pins 1 & 3 give 5V when the car is on MAR and these are the pins that altered the guage readout. Before going ahead and starting the engine, I set the potentiometer to about 2.5K Ohms which should relate to 20degC. This set the engine warning off and I chickened out after that
As for the thermostat pipe, I had to give up before it got fully hot as I had to go out... I'll test this properly tomorrow and let you know how it goes.
On the connector for the sensor though, there are three wires, pins 1 & 3 give 5V when the car is on MAR and these are the pins that altered the guage readout. Before going ahead and starting the engine, I set the potentiometer to about 2.5K Ohms which should relate to 20degC. This set the engine warning off and I chickened out after that As for the thermostat pipe, I had to give up before it got fully hot as I had to go out... I'll test this properly tomorrow and let you know how it goes.
Ok do one test at a time.
Firstly see if your engine is actually getting up to temp with the simple hand on pipe test you've done. See if you can feel the thermostat suddenly open with a rush of heat as before. If it's too hot to keep your hand on then your engine is getting to temp and that's fine.
thermostat working + engine up to temp
Turn the engine off and pull off the eng temp sensor connector and check the resistance across the terminals of your engine temp sensor when the engine is hot and see if it cross checks to the temp v resistance chart
eng temp sensor working
Firstly see if your engine is actually getting up to temp with the simple hand on pipe test you've done. See if you can feel the thermostat suddenly open with a rush of heat as before. If it's too hot to keep your hand on then your engine is getting to temp and that's fine.
thermostat working + engine up to temp
Turn the engine off and pull off the eng temp sensor connector and check the resistance across the terminals of your engine temp sensor when the engine is hot and see if it cross checks to the temp v resistance chart
eng temp sensor working
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Will do...
Out of interest, do the different variants of the Stilo use different temp sensors? It seems strange that you mention yours having two wires and mine having three...
Ooo they cant leave anything alone at Fiat, every version seems different
Wiring diag shows 3 pins but only two wires for eng temp sensor on the 2.4.
Item K36 here
Shows just two wires here but they may have changed things a bit since then
Wiring diag shows 3 pins but only two wires for eng temp sensor on the 2.4.
Item K36 here
Shows just two wires here but they may have changed things a bit since then
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It's weird isn't it... there's definitely three wires going to the connector even though you'd only expect two, with the sensor altering the resistance between the two pins. :chin:
I'll get a mirror in there to have a look at the sensor itself tomorrow to see how may pins it actually has...
I'll get a mirror in there to have a look at the sensor itself tomorrow to see how may pins it actually has...
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I've just had a look on eLearn and it shows K36 as having three wires connected, A2, B1 and B2. I'm sure I had the potentiometer on pins B2 and A2 and it was adjusting the temperature guage on the dash...
Very strange...
Very strange...
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I've been thinking, K36 is shown to have both A2 and B1 as outputs from the variable resistor of the sensor and I have both of them connected on my Abarth... could one be used when in MAR and the other used when the engine is actually running? It might explain why the guage moved as expected when in MAR, but when then engine is runnig and there was no info from the sensor, the engine warning came on.
Just a thought
Quite possibly, A2 looks like an additional separate temp sensor so maybe your system uses that for dash gauge eng temp. On my wiring diag it's redundant and NC = not connected
Post up a wiring diag and let's have a look
Post up a wiring diag and let's have a look
OP
OP
Well... after all of that, the rad fan seems to be working fine. I must have just been being really stupid or maybe the low ambient temperature meant that the fan just wasn't coming on at the time when I first tested my air-con. Either way, the rad fan comes on with the compressor so all that seems to be okay.
As for the thermostat, I'm pretty sure that it's stuck open. It gradually got hotter as the engine warmed up as no matter how long I left it idling, the temp gauge never went above halfway and the rad fan didn't kick in at high speed. I'll get this looked at when I'm certain my warranty will cover it as it shouldn't cause any issues
While I was playing around the engine bay, I noticed I'd dripped oil. This is the first time I'd noticed it since I got it and I was wondering, do these cars usually drip oil or are they quite good and holding onto it? I know they get through oil but I wouldn't expect it to drip any...
I'm thinking it's one of three things...
1) A general oil leak that's been there since I got the car and I've just not noticed it. If so, I'll need to track it down which means getting the engine tray off...
2) A leak that's appeared since getting the car back recently after having the Selespeed sensor replaced...
3) Something I've done...
The "something I've done" is thrown in there because when I took the engine cover off today, I forgot to put the oil filler cap back on before I started the engine. I didn't run it for long as it ran a bit roughly, I turned it off and had a look in the engine bay and noticed the filler cap wasn't on. D'oh! Once I'd replaced it again, the car ran well again. Could this have caused any problems?
Something else I've noticed ( God, it's neverending isn't it!), is that the car doesn't like to sit at a constant amount of revs. If I push the accelerator down to give, say 1.5K revs, it wavers around it a bit, not very much but it's really noticeable. I'm wondering if this relates to the OBD reading I had which said that the "accelerator pedal information" was intermittent?
Any ideas guys?
As for the thermostat, I'm pretty sure that it's stuck open. It gradually got hotter as the engine warmed up as no matter how long I left it idling, the temp gauge never went above halfway and the rad fan didn't kick in at high speed. I'll get this looked at when I'm certain my warranty will cover it as it shouldn't cause any issues
While I was playing around the engine bay, I noticed I'd dripped oil. This is the first time I'd noticed it since I got it and I was wondering, do these cars usually drip oil or are they quite good and holding onto it? I know they get through oil but I wouldn't expect it to drip any...
I'm thinking it's one of three things...
1) A general oil leak that's been there since I got the car and I've just not noticed it. If so, I'll need to track it down which means getting the engine tray off...
2) A leak that's appeared since getting the car back recently after having the Selespeed sensor replaced...
3) Something I've done...
The "something I've done" is thrown in there because when I took the engine cover off today, I forgot to put the oil filler cap back on before I started the engine. I didn't run it for long as it ran a bit roughly, I turned it off and had a look in the engine bay and noticed the filler cap wasn't on. D'oh! Once I'd replaced it again, the car ran well again. Could this have caused any problems?
Something else I've noticed ( God, it's neverending isn't it!
), is that the car doesn't like to sit at a constant amount of revs. If I push the accelerator down to give, say 1.5K revs, it wavers around it a bit, not very much but it's really noticeable. I'm wondering if this relates to the OBD reading I had which said that the "accelerator pedal information" was intermittent?Any ideas guys?
