A new variation on Dualogic faults for me this week.

After a long afternoon on the road (about 3hrs at this point) I'm still 45mins from home when I notice the Red Blinking Door warning and the ever-unhelpful "Transmission - Check Manual" message on the display. The Dualogic 'box is not going above third.

I pull-in, manage to get both 1st and Reverse to tidy up positioning of the car, switch off the ignition. Now when I go to start the car the key turns but there's nothing from the starter and the dashboard console doesn't illuminate. There is power for the windows, interior lights, headlights and radio however.

Call out Recovery. Fuses and relays seem ok, but one relay is getting rather hot when he does whatever it is that recovery guys do. His suspicion is a short. His later suspicion is that the ECM may be "toasted". Recovery guy reports there's no power to the diagnostic plug so he can't get a reading.

I don't recall any jolts or bumps in the road, and whilst it was a wet night the rain only came on after we were already broken down and parked up.

By the way, if you're with RAC or considering RAC - look elsewhere, they're over-worked and you're not going to get a response for 2+ hours on a quiet night. Recovery guy was brilliant (first time I've met a mechanic who owns a Dualogic himself) - but a 3rd party subcontractor, not an RAC van.

At this point I'm aware the car is stuck in-gear. The recovery guy has got skates, but RAC are in no hurry to authorise loading for recovery. I try the usual Dualogic prayer of repeatedly fiddling with the ignition and gear lever - a couple of minutes later I have the car started, gears are selecting (at least 1st and reverse are), I have headlights but no dashboard console - it's not illuminating, the rev counter, speedometer and fuel gauge are dead on the stops and not moving. I'm not going to take the risk the 45mins home now I've got a recovery truck waiting, so it's drive onto the back of the truck and drop-off at the house - where it again manages to start and we can get it off the road.

This morning it's reluctantly starting, there's power to the Dualogic pump (I can hear it), radio, headlights and windows have power but the dashboard console is still mostly dead. I get an initial "N" on the display,it will select 1st gear and move but it does not display "1" on the display. Returning the gear selector to N brings on the Beeps Of Doom which persist even after the keys are removed from the ignition and the doors locked. Eventually I repeat the start-up, the beeps stop.. so I'm calling it a day on this one for now.

I've hopefully got someone coming round later to try and read the codes, Recovery Guy didn't recheck the data port after we got the car started so maybe I might get lucky and we can get a reading with the car running.


I would be extremely grateful for any assistance or suggestions from the forum.

If it's a short, where are the most likely areas to cause a loss of power to the main engine bus and shut-down the dashboard?

The domestic authorities have determined this car must go (she never liked it TBH), so I need cost-effective options that might get the car running well enough for a trade-in, or best options for a spares-or-repairs disposal (2009 1.4 8V Dualogoc, claims to be an Active Sport on the door jamb sticker but I don't believe the Sport bit - probably the only sticker to hand at the factory).



This is likely to be the beginnings of another holiday away from Fiat, at least for a few years

check voltage between gearbox and negative on battery.
If the earth is ok you would see almost 0 zero volts.

That is how you fry ECU's: the gearbox earth gets corroded and all the engine electrics and starter motor and dualogic pump etc get grounded through the ECU's earth, that gets hot the ECU gets hot..etc.

aurick86 said:

check voltage between gearbox and negative on battery.
If the earth is ok you would see almost 0 zero volts.

That is how you fry ECU's: the gearbox earth gets corroded and all the engine electrics and starter motor and dualogic pump etc get grounded through the ECU's earth, that gets hot the ECU gets hot..etc.

Click to expand...

Thank you.

If the ECU was fried, would it start at all? - I know the ECU isn't a cheap repair.

.. and any links to help a technical-idiot know where to put the multimeter probes (at the gearbox end, even I can find the battery!) - assuming I can find my multimeter..

PickleGP said:

.. and any links to help a technical-idiot know where to put the multimeter probes (at the gearbox end, even I can find the battery!) - assuming I can find my multimeter..

Click to expand...

Found the guide..
https://www.fiatforum.com/grande-punto-guides/169204-grande-punto-engine-bay-earthing-points.html

aurick86 said:

check voltage between gearbox and negative on battery.
If the earth is ok you would see almost 0 zero volts.

That is how you fry ECU's: the gearbox earth gets corroded and all the engine electrics and starter motor and dualogic pump etc get grounded through the ECU's earth, that gets hot the ECU gets hot..etc.

Click to expand...

I've got zero volts between -ve terminal and gearbox.

But I've got -0.4V between the -ve terminal and the tin shroud in front of the gearbox? (photo attached, dropped closer to -0.3V as I contort to hold the phone).

With the engine running, the -0.4v to the shroud remains, there's a flicker to 0.1something between -ve and gearbox that wasn't there when the engine was off. Notably it started first time, but the dash console gauges are still dead.

Those measurement seem ok.
the ecu is probably ok.
Do the same voltage check between -ve and ecu housing, with engine running( also while cranking - have somebody turn the key).
Check the connectors next to the battery tray (in the engine bay), spray some contact cleaner...let dry.

Thanks aurick86, with a neighbour's help we got the car to a mechanics this morning. I'm hoping they'll have a chance to look at it early next week.

In Manual mode it was a little clunky on the gear changes (that could be me, I don't usually drive in M) and only went to 3rd. Thankfully the garage was just across town.