Having major issues with my 52 reg Stilo 1.6 petrol.

Here are the facts...

Engine juddering/misfired/erratic rpm prior to cutting out whilst both going along foot down and stationary (waiting to join roundabout) until it finally cut out for good on a slip road.

Luckily I have AA cover and the chap that came out was very helpful. He spent at least 1 hour with me trying things before I opted for a tow home.

Fault codes are:
P0571 - brake pedal switch
P0420 - Catalyser check
U1702 - CAN network
P0230 - Fuel pump CIRCUIT

He cleared the codes and started the car and the 4 exact same codes reappeared after idling erratically for 5-20 seconds.

He had a few problems with the key/lock light in the dash coming up and not letting him start the car - but he locked and unlocked the car a few times i guess to tell the immobiliser that he isn't nicking the car... not sure if this is related.

Ive gone through a few 'above average' puddles in the week at least twice.

Probably worth mentioning also that for the past two days the battery has been totally flat twice when going to start the car to get to work. I didn't know why this was happening and jump started the car with leads. I have since discovered that the reason for the battery discharge is because the radiator fan is stuck on spinning away. In order to stop my car battery draining I temporarily removed the appropriate fuse and drove the car for about half an hour whilst keeping an eye on the water temp dial just incase... not sure if this is related or not.

I'm going to locate, remove and dry out (if needed) the D4 connector tomorrow and cross my fingers. Other than that I think its done for... but there's hope as I know how clever you all can be.

Thanks for any help and advice.
Paz

Hi Paz welcome to the forum, the stilo electrics are very temperamental when it comes to a battery which is low on charge, the first thing is to get your fan sorted there is a guide to fan problems
https://www.fiatforum.com/stilo-guides/104106-testing-radiator-fan-engine-temp-sensor-circuits.html
and brake switches
https://www.fiatforum.com/stilo-guides/100058-brake-light-problems-changing-switch.html
although you main problem seams to be the cutting out which could be linked to your fuel pump error code, but I would try this first before you start taking the car apart
https://www.fiatforum.com/stilo-guides/83260-cleaning-your-inlet-control-valve.html
Have a look at the guides section it's on the blue bar at the top of the page loads of usefull stuff in there
check to see how old your battery is if it's older than 5 years I would be changing it for a new one, this will prevent loads of false warning appearing and scareing you to death.

hope this helps
Karl

Im going to change the brake switch then since its only £5 and the battery is as old as the car (+ I only drive 15 mins to work and back) so im going to change this also but get the more powerful diesel one which i have heard is much better.

Unfortunately I can't really test the temp sensor as described in the help section as the car wont start at all - a lot of the tests using the potentiometer require the car running so i'm hoping the new battery might solve my problems but who knows with the extent of the dashboard disco of warnings and faults.

I just removed the battery and the battery tray was wet and all the connectors under the fuse/relay box appear to be wet also.

Having left the fan fuse unplugged in over night I was suprised to find out that the battery is flat again so many this has something to do with it being wet and discharging all the charge- I don't know! :bang:

I am going to dry everything out and charge the battery- may as well take the D4 connector apart whilst I'm there and properly dry that out too.

Any other ideas?

A new battery is on order - meanwhile I have charged the old one fully (don't know if it will hold on to its charge?

This morning I can't even try to start the car due to 'car security failure'???
tried locking unlocking and disconnecting battery for 5mins.

as well as asr and abs failure... theres a new message: loose connection failure

Iv'e no idea what's going on now! - Doesnt help that its pouring with rain either

Does this all mean anything to anyone?
Thanks

pazstilo said:

A new battery is on order - meanwhile I have charged the old one fully (don't know if it will hold on to its charge?

This morning I can't even try to start the car due to 'car security failure'???
tried locking unlocking and disconnecting battery for 5mins.

as well as asr and abs failure... theres a new message: loose connection failure

Iv'e no idea what's going on now! - Doesnt help that its pouring with rain either

Does this all mean anything to anyone?
Thanks

Click to expand...

A new (or fully charged battery) should hold 12.6 volts - if not it's dead, to make it easy.

You might want to change the battery in your key, as this transmits signal to disable the "start-blocker". Do you have another key?

Yeah, ive tried my other key and the same thing happens - car/padlock icon on dashboard that flashes for a bit then once I crank the engine a few times the icon is on constant and the display reads 'car security failure' (Among other warnings/failures as mentioned above).

It's pretty clear your issues are related to water mixing with the electrics (will be surprised if a new battery is of much help).

The problem is that this will quickly turn to corrosion whilst any form of dampness remains which I suspect is the cause of the "loose connection" error.

How come it's got so wet - have you not got a battery cover

We'll it has a cover but a year ago i had problems that meant i had to keep taking the cover on and of and on and off all the time so (stupidly) i left the cover off and never got around to putting it back on - so i only have myslef to blame. Very naughty I now realise!

On the way to work (and due to the recent storm in the south at the end of last week) theres a huge unavoidable puddle in the road - another car drenched me on wednesday as he went through doing probably 30! + the next day I came off a roundabout and took an immediate left into a huge (windscreen covering) puddle which i wasnt expecting. (This was Thursday; Friday morning was the first time i woke to a flat battery by the way!

So do you think, take it to bits dry the disconnect-able parts on the central heating/radiators/airing cupboard?

I also bought some electrical contacts cleaner. should i use that?
The connectors don't look particularly or visibly wet by the way...

could a specific part in particular be wet to cause the radiator fan to be on constantly?

Thanks

You have propably answered your own questions. Water is most likely the issue. I jetwashed my Stilo (from the outside) and into the left front wheelarch. The car didn't start afterwards... So now I'm on sponges and soapy water.

Dismantle the fusebox and clean it, look for "bigfathairybikers" post where he has pictures of it.

The fan is propably a fault on its own. The switch might need a cleaning, as it operates on two speed levels.

Hi Paz the dash warning were exactly the same as I had last december, got the AA out and they put a MIG WELDER on to give my battery a boost and all worked fine with it running, drove it home left it for an hour and all the warning came back on and it wouldn't start, put a new battery in and no problems since and I ran an extra earth to the engine block just to make sure.

Karl

Yeah - I'm convinced the battery has something to do with it. The battery is as old as the car so I would have needed the new one sooner or later.

Fingers crossed! (I've been hearing that phrase a lot recently lol)

Still no joy

I have connected the new battery and cleaned and dried the D4 connector along with other connectors, but I can't test the results as the 'car security failure' isnt allowing me to start the car. Does anyone know how to get around this? i bought a fault code PC interface from ebay if that helps???

I get the same error messages in the dash but i expect they will stay until i clear the codes via the code reader.

Thanks everyone

pazstilo said:

Still no joy

I have connected the new battery and cleaned and dried the D4 connector along with other connectors, but I can't test the results as the 'car security failure' isnt allowing me to start the car. Does anyone know how to get around this? i bought a fault code PC interface from ebay if that helps???

I get the same error messages in the dash but i expect they will stay until i clear the codes via the code reader.

Thanks everyone

Click to expand...

hey pazstilo, apart from the fan iv got the same problems as you but iv not drove through any big puddles, saying that it has been raining heavily up here. i got the security problem twice in 3 days, the way i got round it was to get out of the car and lock & unlock & opened the doors a good few times with the key because my key fob hasent worked in the past 2 months. eventually the car realised i had unlocked the doors & got in rather than it thinking i had broken in the window & tried to steal it! when security lock was on i heard a constant ticking coming from the drivers rear quarter panel or wheel arch area, i think there is a sensor or module there to aid in the security system (could anybody elabirate on that?) i checked the earths today & they were fine but the battery is six years old & when checked under load it only had 2volts (should have about 14 i think.) i think thats why the central locking isnt telling the car when iv unlocked & entered, the battery is too weak. new battery coming my way soon, hopefully it sorts my problems. good luck

After a long absence, i'm back with more news.

I had my car taken to the local Fiat (i know, sorry) It was sat on my drive for 3 months or so rotting away so after saving up a little money i decided to get it looked at.

They have come back to ma saying that the under bonnet fuse box was a mess and corroded and that their diagnostics would not work and that they had to replace it - fine.

Their solution to my problem is that they want 561+Vat for a new ECU ant that fully fitted all in cost will be ... wait for it £950 and they wont gaurantee that it will fix the problem.

Given that I can get an ecu from ebay for about £150 (although there are none on there at the moment). Can the ECU be programmed by some one out of the car or does it have to be in the car to be programmed because i would like to get the car towed back to mine and get my own ECU rather than pay £950.

Any thoughts?

Use the search! Flyright put a new ecu in their 1.6 within the last few weeks

The ECU doctor sent me this information...

Thank you Pascal for your email and valued enquiry.
In early 1999 this manufacturer moved to using a later generation type ECU in their product range. It is a slim tile shape and mounted on the engine.
Because of the construction and being filled with an epoxy type resin it is not considered serviceable (or even testable with our equipment).
Also employing wire bonding technology and a thick film circuit makes additional problems for any re-engineering attempts.
Although not able to assist directly we have looked out some other company contacts below who do similar work to ourselves. Probably best to say you have seen their respective website when phoning.
Reason being if they can service your enquiry, if they know we could not, that company may have price leverage on a quote for task!
With regret at not being able to assist directly,
Kindest Regards.

Where does this leave me now?

the 1.6 Stilo with the Fiat engine (not the later model with the Opel engine) has a Marelli 5NFT1 ecu which has a rather conventional setup , not filled with epoxy resin nor equipped with thick film circuits - it has a normal circuit board with conventional (smd) parts.
I guess they have the Marelli 59F ecu in mind, that's a horrible construction regarding opening or repairing but this ecu is not used in the Stilo afaik....

I'm up and running. it's been a white and forgot to update this post.

Anyway… BBA reman took my ECU for examination free of charge for diagnosis.

They advised me that for around £300 they could repair and refinish my own ECU and was delivered back to me good as new with full instructions on how to initialise the thing (revving the engine etc) - it was also recommended by BBA that I replace my coil packs as it was possible that they may've been to blame - I didn't want to risk it, so replaced them all.

All my fault codes and gremlins seem to be sorted for now.

Good luck to anyone else with similar problems - it seems that every case of fault codes has a different root cause.

Thanks to everyone for their help and advice
Pascal

Worrying as i got similar problems to what you described the loose connection engine cutting out security failure car not starting batery is at 14v alternator checked out ok.got to wait until the weekend for advanced diagnostics.

You recommend bba reman then?