Just ordered a second hand ABS ECU and a ripped off connector. Will solder me an interface, so that I can measure ...
- ... from the ECU's mass (Pin 38 and 13) to the batterie mass and ...
- ... from the ECU's alimentation (Pin 1) to the batterie plus (resp. the fuse) ...
while actuating the valves.

This is not work, this is sports!

BlackForest said:

Just ordered a second hand ABS ECU and a ripped off connector. Will solder me an interface, so that I can measure ...
- ... from the ECU's mass (Pin 38 and 13) to the batterie mass and ...
- ... from the ECU's alimentation (Pin 1) to the batterie plus (resp. the fuse) ...
while actuating the valves.

This is not work, this is sports!

Click to expand...

Hi There BlackForest!

I have been following this thread with great interest and am impressed at your determination and enthusiasm for this "sport"!

I have a personal interest myself owning a 2013 4x4TA and having experienced similar symptoms to you (4x4 unavailable, warning lights..etc). I am also interested in your MultiECUscan diagnostics equipment and have a couple of questions which might cause you to reflect on the interpretation of the data you are reading with it.

My question centres around what frequency the MultiECUscan system samples at when you are using it "live" (I mean when the vehicle is running and especially when you are driving it)? I have attached a couple of your own images and highlighted the time stamp which I assume is in seconds?

If these are actual data points then I would suggest that the frequency of sampling is way too slow if compared to the frequency at which a typical engine management/body control computer in a modern car runs at (although I am happy to be corrected). If this is the case then there is a real risk that you not not capturing anything like the reality of what is occurring (is this referred to as aliasing?). I make this statement from a reasonably informed position having designed development test data acquisition hardware using programmable software. Again I don't know the capability of the MultiECU scan package but I had always thought of it as a diagnostic system for reading and resetting codes rather than an on-line data acquisition unit? Again happy to be corrected by those better informed. Certainly ECU/BCM hardware must run kHz frequencies I'm sure?

So my point? My point is that you may not be measuring what you think you are or the measurements may not relate the actual situation, witness the crazy abs wheel speed data (unless you were driving on two wheels?) :slayer:

Finally I would refer you to my experiences (and earlier post) since this is what I know! I had all sorts of ABS ESC and 4WD messages until the brake light switch and battery voltage sensor were replaced (not scientific I know - changing two things at once) but normal 4x4 service was resumed, and I still don't know why!!

Good luck with your continued pursuit of this issue and do keep us informed of progress.

Im still amused /bemused that it had more than 1 part swapped.. which was the ACTUAL component at fault..?

However great to know it cured your issue..
And they are simple bolt on components

A cheap experiment compared to 4x4 kit


Updates eagerly anticipated



Thanks for studying the live data...
(On my phone this stuff is just too small)

I dug out my old MES to attempt tracing an electrical running issue on my Panda TA.. but fixed a 500 TA Instead..

Charlie

The op has been inducing wheel spin on slippery surface in order to see if the 4x4 system operates. So one wheel near zero and the other spinning on sloppy surface likely to result in the observed wheel speeds.

varesecrazy said:

Im still amused /bemused that it had more than 1 part swapped.. which was the ACTUAL component at fault..?

However great to know it cured your issue..
And they are simple bolt on components

A cheap experiment compared to 4x4 kit


Updates eagerly anticipated



Thanks for studying the live data...
(On my phone this stuff is just too small)

I dug out my old MES to attempt tracing an electrical running issue on my Panda TA.. but fixed a 500 TA Instead..

Charlie

Click to expand...

With a little further digging, bizarrely, it appears to have been the brake light switch that messes with the ABS ESC and 4x4 systems (at least the electronics/algorithms controlling these systems). The (so called) intelligent battery sensor, IBS, (voltage controller on -ve battery terminal) revived the Stop Start (not something I was fussed about).

The diagnosis of the IBS came about as I was also reporting a repeating drained battery, the actual issue is, I think, a failed Blue & Me unit which doesn't realise that the car is locked and fails to shut down, but this, as they say, is another story!

There are other threads on here that have connected a dodgy brake light switch with ABS, ESC etc warning light issues but I haven't yet read a plausible reason, and for the record my brake lights were still working! It's worth pointing out that none of the warning occurred until the first touch of the brakes following start up, i.e. turning off and on reset the system - nothing like a good reboot!!

The system is quite creative in its use of data from sensors such as the ABS system, somewhere else on here someone describes the tyre pressure sensing which actually uses different wheel speeds (deflated tyre rotates at different speed) and therefore triggers a faulty tyre pressure. I indirectly experienced this ('63 model without tyre pressure "sensing") where my daughter drove a few miles home with a total flat (4x4 will pull you through anything!) and she reported that the car had a 4x4 and ESC warning!!

I dooo realise that not all of this experience relates to the OP, but I'm trying to point out that maybe things are not always what they seem...

Especially when it comes to Italian car electrics/electronics!

I believe there are effectively two switches in the brake light switch. One that operates ‘normally’ and turns the brake lights in when the pedal is pressed, but the other is ‘on’ when the pedal is fully up to report that the pedal has returned. Another post somewhere here suggested the loss of the ‘returned to up’ signal led to the errors being shown.

:yeahthat:
And not just on Fiat's (or other Italian cars).

gr J

Herts Hillhopper said:

I believe there are effectively two switches in the brake light switch. One that operates ‘normally’ and turns the brake lights in when the pedal is pressed, but the other is ‘on’ when the pedal is fully up to report that the pedal has returned. Another post somewhere here suggested the loss of the ‘returned to up’ signal led to the errors being shown.

Click to expand...

Thank you! Now that starts to make more sense; what havoc a £12.00 part can cause!

Well guys,

thx for all the input. Everything reasonable. Will have to reflect all of your input.

Only loosely related to this thread some age old experience of mine: Begining 80th we made an business simulation at the university. Among quite a few of parameters there was one, which was documented at "not used" and it was named something like "other expenses". For the sake of fun, I did order there a "box of champaign". Expected behaviour was: None. In reality, the whole algorithm went havoc and none of the restrictions like "storage capacity", "max production capacity" and the like was checked anymore and we won the game.

Long story short: With computers and your spouse (in pre-PC days I would have written: women) never assume anything.

BOT: Earnestly considering as a plan B to replace the mentioned parts, even so it would mean to surrender intellectually. The winner ...

Thx so far!

BlackForest said:

Well guys,

thx for all the input. Everything reasonable. Will have to reflect all of your input.

BOT: Earnestly considering as a plan B to replace the mentioned parts, even so it would mean to surrender intellectually. The winner ...

Thx so far!

Click to expand...

Give the brake light switch a go, there seems to be a common theme?