Technical Stilo with countless faults (mostly electrical) please help!

[dhunt]

Right well i bought my 02 plate 1.2 stilo in late december. Since then there have been 3 major problems, 2 which still need sorting and 1 which I really need to drive

I suppose its best to start with the most important, when i bought the car it had just passed its mot on the fact the when you turned the key the first time it came up with the power steering not on and a message "loose connection" but if you turned the key back to off and then on again quickly it was fine.

This lasted untill recently when it just wouldnt start and so as to advice on here i changed my battery to one of my fathers ones, after that it was fine up until the other day when it went and just wouldn't come back on. Got it to an independant garage (spiros as recommended on here) where the friendly mechanic managed to tell me that after the tests all was fine and to see if it came back. Then today it did it again, I phoned him and he said hed want to see it again but changing the battery again may help. I am a bit confused here and want to know if anyones been through the same?
^ This problem if anyone has any knowledge of would be much appreciated as I really need the car to drive tommorow!

Second is both rear doors being deadlocked, i tried every trick on here in every thread over 100 times and then took it to a fiat garage to have it tested and they said both the rear door locks had failed and i would need new ones and a stupid labour cost. Have survived without the rear doors since january and now having the rear door locks as purchased from ebay i cant find anywhere to give me a labour quote of under £300/400!

Third was a engine misfiring but engine seemed to be fine when i replaced the pistons on the cylinders that it said were misfiring although i have noticed the ocational judder like it did before this happened last time.

have enclosed two pictures, one of the loose connection message and the two lights that come up when i turn the engine on and another of all the lights at just the engine power stage!

 

[dhunt]

Also the sheet from the diagnostic test for the misfire shows the electrical problems on the car! The list goes:
9037 - Cigar lighter and air cond light S.C to +batt.V - present
9019 - Boot opening relay S.C to +batt.V - present
9025 - Optional services relay, S.C to ground - Present
9029 - Serial line W, Communication error - intermittent
9018 - RH rear foglight, O.C or S.C to +batt.V - intermittent
also
Control unit power supply value too low - Intermittent

Since this is my first fiat any knowledgeable input is more than welcome!

 

[Deckchair5]

Well, perhaps unsurprisingly, you have a loose connection
loose connection= lost or poor connection
when your mechanic looks over it then the problem most likely isn't present = no fault found. Simply changing batteries isn't the way to go, you need to find the source of the poor connection

when i bought the car it had just passed its mot on the fact the when you turned the key the first time it came up with the power steering not on and a message "loose connection" but if you turned the key back to off and then on again quickly it was fine.
So you know the fault is in the main power (battery and alternator) supply and earth. First thing i'd do is clean up the battery to engine earth connection. Have a look in Stilo Guides for what to do. 9/10 power circuit problems start there

All the other faults are open circuits or short circuits but they're meaningless if the car hasn't got a stable power and earth supply for reference

 

[dhunt]

Thanks for the input I will do to check them using the stilo guides now, only reason I didn't do it as in the garage the mechanic said he had checked this. The summary sheet says
"Carried out checks for power sttering not working, checked supply voltages & signals to power steering ECU, recharged vechile battery & tested, found power steering ok after battery charged, customer will take vehicle and see if fault persists"

Also if the battery has a little more ampage than the one that was in the stilo before would this affect it at all and would i be better with the old? will let know if things are still the same after looking at the battery to engine earth!

 

[Deckchair5]

A loose connection is a loose connection regardless of what power of battery you have in there. It's a voltage circuit problem and not a current (amp). Checking voltages when the car is running with no faults won't tell you a lot as your mechanic found. Voltage drop testing across components with engine running when the fault is present will identify the culprit if you can find it but there's not many connections in the circuit between the alternator and the battery

If you do a voltage drop test with good connections from the battery neg to an engine earth point then a sudden raise in voltage in the fault condition identifies the battery bad earth ...... or you could just get straight on it and clean up the battery neg to engine earth point

 

[dhunt]

Ok thanks well with that i just spent ages in the darkness with a large amount of torches having a go at the main battery engine earth and charged the battery whilst doing this. After I put everything back together and turned the car on it came up with a loose connection the first time but after turning it on and off it has been gone for every turn and a few little test drives!

Hoping this solves it but cant feel a bit reminiscent of the same thing that happened after the garage had it. Will do all the earths with new cabling if that is what is most likely going to solve the problem forever when more light and time is available! Thanks for your help its much appreciated, Daniel.