My friend has an 04 Stilo JTD. It has always had electrical gremlins that come and go at random times.

However it has lately been complaining about an ABS failure.

So I plugged my generic code reader in to check for any DTC's, however on plugging it in the car goes haywire. Yellow warning triangle, red steering wheel warning light, ABS failure light, car with padlock symbol all flashing on and off and loose connection ( I understand the loose connection means that communication is being lost between various ECU's?) oh and the fuel gauge goes up and down.

Clearly there is something not right here and it always complains of some electrical problem somewhere every now and again whenever it feels like it.

As far as I know the battery is fine but I know a bad battery can cause issues so might try and rule that out, but there are no problems starting or discharging of the battery.

As you say be good idea to rule the battery/power side out first that are know for causing electrical issues, checking voltage at charge and stand still, also earthing points can become corroded so would check and clean up those and as well as battery terminals check tightness and clean..there is also the D4 connector behind the battery fuseboard that become damaged by moisture/dirt so checking that is ok also, if you are checking battery and terminals and remove battery to check D4 connector this would also help as having the battery dis-connected for 30min can help to reset car computers and at times remove any random electrical faults
info on D4 connector can be found in guides section link below, some other useful guides there too.
https://www.fiatforum.com/stilo-guides/99828-d4-connector.html

Well I have just swapped the battery off my 54 reg MG ZTT and it still has the same problem, my battery is fairly recent and my car will cause havoc if a poorly charged battery is fitted if it even starts, ifthe voltage drops by a few volts it wont be enough to start my car so I think I have ruled the battery out fairly conclusively. my multimeter is broken so unable to do a check with that.

So looks likely to be an earth or dodgy connection somewhere, not having a fuse box cover over the battery compartment probably does not help and I have been telling her to buy one since she bought it but you know what women are like when it comes to cars. Will also check this D4 connector you mention. Is there a guide to this.

Checked the D4 connector and the pins are all clean and corrosion free, the cabling all seems to be in tact also. There is a bit of muck on the outside and on the cabling but all the wire grommets are present to keep muck out of the holes. The connector goes together fine and all seems good connection wise there.

Something is really sending it haywire especially when I plug my OBD reader in, which it never did before when I have used it. interestingly it is reading live engine data OK, is it just struggling to connect with the engine ECU? Hence no fault codes stored?

Good you said about not having a battery /fuseboard cover that can cause no end of problems and very prone to water damage i.e shorting relays and connections if you look in guides there is also info on drying out the fuse board, I only left mine off for a a couple of days while checking battery condition and got caught out in the rain , it did not cause same errors you have but cannot predict where the water will short, so very much worth checking also and getting a cover for if you intend to use car in the rain
Which code reader are you using , it may help to know if others have had issues with same reader, I have used a budget one (orange colour type) and multiscan software with no issues in connecting

Wholeheartedly agree on the fuse cover missing and have tirelessly told her to buy one, having said that the car gets plenty of use in the rain and does not have half the electrical problems I would've expected. I could remove everything relay and fuse wise from that board and make sure everything has a good contact there. Next plan of attack to check all that.

I have checked the fuse board by cleaning all the relays and fuses of any corrosion, only 2 or 3 relays had corrosion and connections look fine yet again. Will see if that makes any difference once it goes back together.

Have plugged my OBD reader its a Maxiscan 509 I think into my car and working fine as it brings up Mass air flow circuit low which I expect with a dodgy MAF and currently unplugged. So yeah seems the reader is OK. However I now have the Stilo battery on charge, I only have a cheap and cheerful charger but it was showing only 10% charge in the battery so will charge it and see how it goes if it makes any difference.

Evening

Reading though your posts, if i try and connect my code reader while the ignition is on or engine started, mine goes mad with "loose connection" only found this out by accident.

another thing about the code reader, i bought one, it came up with the same code but 2 different meanings. but FIAT Multiscan brought the same code up but with a better meaning. try cleaning it with some Electrical solvent cleaner from maplins, or the hose rubs on the n/s/f plastic arch which could be low boost.

If you find out the hose/pipe is split and know the part number or price is your getting one let us know!

Paul

paullawton2007 said:

Evening

Reading though your posts, if i try and connect my code reader while the ignition is on or engine started, mine goes mad with "loose connection" only found this out by accident.

another thing about the code reader, i bought one, it came up with the same code but 2 different meanings. but FIAT Multiscan brought the same code up but with a better meaning. try cleaning it with some Electrical solvent cleaner from maplins, or the hose rubs on the n/s/f plastic arch which could be low boost.

If you find out the hose/pipe is split and know the part number or price is your getting one let us know!

Paul

Click to expand...

Interesting you have had the same problem with a generic code reader. The MAF problem is on my own car an MG ZTT not the Stilo just checked to make sure my code reader was not faulty.

It needs the ignition at position 1 for the code reader to connect to the car. Even trying turning to position 1 with code reader trying to connect it still makes the dash warnings go haywire. So I'm still no nearer to figuring this out. Have charged the battery as well so don't think its a power issue unless its a bad earth somewhere.

If the fuseboard cover has been missing for sometime it would worth effort of looking into, just remove fuses relays place on piece of paper marking which slot removed from and if you have multimeter test each fuse when putting back together, once fuses relays removed the fuseboard can be taken apart to dry and check, when mine caused a problem from rain, the water had caused a short along the circuit board of the fuse board as there is a fair bit of current going through the board along with earth lines I was able to carefully clean up the short on the board and been fine since but do not leave cover off at anytime now..others also have had issues with no cover so well worth a look at..

I have had fuse board off and apart, tracks etc seem OK. I have continuity from the main power feed from the battery to most terminals I expect, ie each fuse position has one contact testing OK for main power and the other not giving any reading as I would expect. Condition inside is not great but looks OK to me.

I assume this can't be taken apart any further than I already have to check the underside?

I'm not great with electrics or electronics myself.

It does come apart in to further layers , although there is no signs of shorting, burnt connectors or between circuit lines, and if you did not have any water run out I would think it would not be an issue , you would certainly notice any shorts by blackness caused by the heat of the short circuit..and if it appeared dry, then have to think on what else, as battery charged as you say..anyone you know with a different code reader so can rule any compatibility issues with the reader and fiat electrics out, just a thought....I have used a cheap one obd reader and connected ok but could be worth a try with a different one to be sure, as although you may have some other faults it is when trying to read them the dash goes warpy..a different make of reader may connect ok and be able to read any codes..

Thanks for the reply buddy, did not want to force it further apart as it felt spring loaded. But no water at all dry as a bone. Having said that I have plugged my code reader in again and removed one of the relays and it brought up an error code for fan 2 control which I have been able to clear subsequently so it is reading ECU error codes. It obviously cannot communicate with the ABS ECU I know a higher model of the Maxiscan does communicate with a lot of common ABS modules. So on the basis that is currently complains of an ABS failure (already had a new ABS sensor on the drivers side front wheel) and it is only when I plug the code reader in everything else goes haywire I'm thinking a bad earth somewhere, checked the ECU wiring harness as well for any damage just in case. Any ideas on earths I can start checking that might be obvious for the CAN BUS as I assume that something is messing the signals up on the CAN BUS somewhere, maybe the BCU? Where is the BCU located? I should add it goes haywire while looking for the protocol to connect to the ECU, before even checking for any error codes, I can read engine error codes and clear them so it is working, I have also used this code reader on the car before and it never made it go into meltdown before.

Just quick question when you say you have used the code reader on the car before was that to read ABS codes ..just that for certain systems on the fiat I use Multiscan software link below and when connecting to certain systems it is explained better in the link , the obd connection needs modifying by soldering a wire to another pin of the elm obd device, only add this in case you can connect ok to certain systems and not others and may be the reader not being compatable for the abs system..anyway multiscan link below with some details of the modifications to connector which may help although not suggesting you should modify your reader if it is the case
http://www.multiecuscan.net/SupportedVehiclesList.aspx

sorry not able to help with which earth is related to can system I just went round mine cleaning up every earth I could find
ooh and homepage for multiscan software
http://www.multiecuscan.net/Default.aspx

Not for ABS issues no as I forgot it would not read ABS faults but just to check for engine ECU faults like MAF and reading live data etc which it does work for that. Like I say it is when it is checking for the protocol to connect that is starts going haywire and causing all sorts of issues, first off I want to be sure there is nothing wrong on the communication side before I start looking for an ABS fault just in case it is a red herring.

I have a Stilo that I need to work on (it's not mine) and there are similar problems when I connect a diagnostics cable. The cable pushes into the (in-cabin) fuse box as this is also the body computer. The top fastening is missing from the fuse box and as it flexes, this seems to bring on the problems (Loose Connection, ABS/ASR failure). So, I'm going to check the wiring for the large multiplugs (loose terminals, maybe), and plan to strip the fuse box/body computer down to the circuit board, as there might be broken solder joints.

Sorry this isn't helpful (yet), but just wanted to let you know that I'm facing a similar problem myself, where the action of pushing the cable in seems to trigger off all the faults. Previously they would go away after a while, but now I have the faults most of the time. I think the problem lies in that area - the lower-right corner of the dashboard.

-Alex

Interesting post but the fuse box on this one seems solid enough. Like I said before as soon as the code reader is connected it goes haywire. I haven't really got round to looking into it any further yet. All I do know is she has bought a proper lemon. There is always something going wrong with it. And everything I look at to fix has been badly fixed by a DIY wannabe by the looks of things I find. An example the intercooler hose pipe had been badly taped together to try and fix it for the sake of a £90 part. The headlamps need replacing as the adjustment screws are broken and one motor does not work and the other just whites away all the time doing nothing. Not to mention screws/bolts that have been left out. Had to replace the fuel junction box as it had a diesel leak, it had been damaged and badly repaired with some type of expoxy resin so was going to give up alogether at some point. I'm all for emergency fixes sometimes but they are usually not a complete fix and will tide you over until you can afford to replace said part. Just seems the more I work on it the more it has been bodged and neglected.