Hello,

I just bought a Stilo Abarth with some electronical issues. It was very cheap, so I didn't care about it, but now I can't find the root of its issues.

It has the typical loose connection error, but after reading all of the other threads and trying some stuff, the car is still inoperatable.

As soon as you turn the key to MAR, it's giving me a lot of errors. ABS, ASR, ESP and gearbox failure, paired with loose connection and car safe (sorry, don't know what it would show in English, in German it's "wagen sicher", so immobiliser). Trying to start the engine, it will crank but not ignite (because of immobiliser error I suppose).

Sometimes the engine will start (maybe a 1/20 chance), but will shut itself off within 30 seconds with all the errors again.

Guy before me said it started when putting a new battery in, but I don't know whether that was the truth.

What I tried so far:
- tried two different, fully charged and rather newish batteries
- disassembled both fuse boxes and cleaned all the layers and connector pins
- disconnected all connectors (including D4) in the battery area, spraying them with Nigrin contact cleaner from the inside and letting dry for a day
- checked fuses and relays
- checked the earthing points I could see and reach from the top. Only one I couldn't get to was the engine earth next to the airbox. Seems I should easily get there from under the car, but didn't have a jack with me

So where should I go next?
I already ordered some fiat diagnostic interface and new/additional grounding lines, but they didn't arrive yet.
I'm running out of ideas...

Parts arrived today.

Using Multiecuscan and a modified ELM interface, I can not access the ECU (is it shot?), but the Selespeed Module.

It gave the following fault codes in blue writing:
- P0720 Transmission/Gear Sys (12) : invalid signal
- U1706 CAN network (NCR-NFR) : no signal
- P0725 Engine speed signal : no signal

And the following fault codes in red writing:
- P1760 Brake pedal switch : invalid signal : fatal : light on
- U1701 CAN network (NCR-NCM) : no signal : fatal

Is it only because of the brake pedal switch?

If you're having problems accessing the ECU then it could be knackered, although the problem might be simple to resolve (one or a few loose pins).

If it's not communicating with the Body Control Module then the immobilisor will be activated so the beast won't start. You might get strange messages on the dashboard if the BCM also can't complete its checks.

I would take out the ECU and then look at that closely to see if it appears damaged. You might need to use a professional to diagnose whether it appears to be fine or not.

The BCM would be the next thing to check, in case the BCM is failing to talk to the ECU for some reason but the ECU is actually okay.

The immobilisor is on the BCM. If you need to replace the BCM then you can transfer your chips onto the new BCM so that the immobilisor still recognises the original ECU.

If you need to replace the ECU then it's more tricky. You can get the ECU, BCM and key (for the transponder) from another car as a set and fit the whole matching set. You can swap the key blade from your old key to the new key so that you can operate the doors and ignition lock.

But anyway, first make sure the ECU is okay and then the BCM. The problem is one or both of those for sure.


Ralf S.

ECU looks "normal"...no bent or pushed pins. I actually opened the black backcover and couldn't see or smell anything unusual.

Will have a look at the BCM soon.

Are there any relays or fuses for those modules on the abarth?

I don't know which specific fuses power the ignition but it's probably that circuit. I don't think they have their own fuse or relay. But I think fuses/relays is a red herring. There's some kind of connection going on but with errors, so it suggests the fuses/relays are fine.


Ralf S.

Some more thoughts:

- changed the brake light switch today but even after code clearing the fault code is still there (invalid signal)
- turning MAR/ignition on, the radiator fan immediately starts spinning, first on low speed, then going full speed after a few seconds
- there is no voltage between negative battery terminal and engine or ecu with ignition on, so grounding seems to be good enough

Could start the engine again today, idled fine, took throttle fine. Shut itself off after about a minute...no more luck after that.

Pretty frustrating...

Another thought: scanning for available modules in MES, it won't show either the ECU or an ABS module, but Body and Selespeed modules (as well as some others). Doesn't it show the ABS module because you need an adaptor or because MES can't see it?

I think I heard about ABS and ECU being in line in the CAN Bus system, might that be a clue?

Are you sure your mod on elm is not interfering cause you should be able to see engine ecu with an unmodded elm

The elm interface was sold on ebay as "modified for multiecuscan" for Fiat, Alfa, Lancia by a vendor.

Maybe you can find someone else with elm near you that you could try

I think the ECU/ABS modules not being seen by MES actually could hint at a problem within the CAN network itself instead of a faulty ELM interface, but that's just my opinion. Furthermore, the Selespeed module showed a communication error with the ECU, which kinda proofs this theory.

What I don't get is why even with a new brake light switch it still throws P1760.

Then check the bcm cause the bcm is responsible for the brake lighs

Yes, BCM controls a lot of the circuits. My old beast had non-working high beams when I bought it, which I thought would be a simple fuse or wiring issue... it turned out the BCM had a burnt track, so I had to replace it.

For high-beam, the stalk sends a signal to the BCM and the BCM lights up the little blue light on the dashboard on one circuit, and also turns on the high beams using a different circuit. I was used to "analogue" wiring... so I thought the blue light means the circuit is okay, so it took me a while to work out what was wrong.

I changed the BCM but because of the immobilisor, it's not 100% simple.

You could buy a spare BCM (they're pretty cheap - nobody really wants them as they are largely "useless" to most owners). Put it into your car just to see whether the car electrics look okay.

If it looks like it's fixed the problems then all you would need to do is swap your BCM chips to the new BCM (your car's immobilisor codes are in your existing chips). Then it will just work (no need to re-program the ECU or get different keys etc.)


Ralf S.

Took the BCM out today and opened it up. Didn't see anything unusual.
There was a little bit of green corrosion on a few pins inside the BCM, cleaned it up and put it back in. No change.

Bought the registered MES version too and scanned the BCM.
Fault Code B1029 Serial line W.

Proxy alignment says Engine control node (ECM/NCM) removed. Everything else is marked OK....

There's one thing I don't understand: why does the engine start sometimes? Why did it all start with a new battery? I don't get it.

So one more question...if I get ECU+BCM+Key from the same car, will it work together? Or will I still need to virginize the ECU?

Anyone know the difference between BCM NBC192.01 and NBC192.51? Can't find anything...

In case anyone has the same issues in the future: ECU was completely dead.

Put in another BCM, still no ECU detected. Put in another ECU, only fault code left was brake light switch. So I re-adjusted my already installed new switch, did a proxy alignment and everything is fine again.

alkali said:

So one more question...if I get ECU+BCM+Key from the same car, will it work together? Or will I still need to virginize the ECU?

Click to expand...

If you have those three items, they will work together.

You can transfer the new key chip into your old key (or put your old key blade into the new key, if that's nicer) so that you don't have to change any locks.


Ralf S.

I had 89 errors when I got my Abarth stilo selespeed.
81 fixed with a new battery clamp.
7 more with a new battery. Make sure is has the correct one and not a cheap small one like mine had. It is one with recessed posts.

The last error required a new gearbox computer but at least the car was driveable by that stage.