Technical Do I need to get my ECU reprogrammed/repaired?

[koalar]

Yes multimeter fine

The diagram is the whole code immobiliser system

The big bit is the body computer

Everything is within the car except the two wires circled the small box underneath is the ECU

Of cause if the ECU isn’t powered up or grounded it can’t communicate the code back

 

[koalar]

Bit obvious

You have put the earth strap back on the gearbox

Is the battery tray bolted down

 

[WildFeraligatr]

Bit obvious

You have put the earth strap back on the gearbox

Is the battery tray bolted down

Yes and yes

Battery is still charging so I'm having a play around with the fuses and my multimeter

 

[koalar]

Yes and yes

Battery is still charging so I'm having a play around with the fuses and my multimeter

Thinking back

You mentioned the oil light is working properly

This is powered direct from the ECU so must have power and ground

If you pull the oil pressure switch and measure between the chassis/engine block it should be very close to 5V

If the battery is weak it will fail with a U1600 code while cranking as the voltage falls below that needed for the body computer

 

[WildFeraligatr]

Thinking back

You mentioned the oil light is working properly

This is powered direct from the ECU so must have power and ground

If you pull the oil pressure switch and measure between the chassis/engine block it should be very close to 5V

If the battery is weak it will fail with a U1600 code while cranking as the voltage falls below that needed for the body computer

I wouldn't be surprised if it was a weak battery, it took most of the day to charge!

Unfortunately I have a coolant leak to fix before I get the battery back in so won't be able to update until that's done (probably next weekend unless I get some evenings free this week). I'm not sure on the etiquette on this forum, can I update this thread once I have some more info or should i create a new thread?

 

[Pugglt Auld Jock]

I wouldn't be surprised if it was a weak battery, it took most of the day to charge!

Unfortunately I have a coolant leak to fix before I get the battery back in so won't be able to update until that's done (probably next weekend unless I get some evenings free this week). I'm not sure on the etiquette on this forum, can I update this thread once I have some more info or should i create a new thread?

No, please keep this one running.

 

[koalar]

I’d keep it all in one place

Then anyone who already contributed to this thread will get an alarm that there is updates

I found the cam timings for the 1.2 panda and VVT 1.2 although the exhaust is quite different the inlet was only around 1 degree different

I couldn’t find the specs for the euro 3 and 4 so it’s still fingers crossed and pray

Learnt something new today the timing for the 1.2 4x4 was different to the standard 1.2. I understand why but surprised Fiat went to the bother.

 

[WildFeraligatr]

Thanks chaps, I'll post again here once I've got an update!

I couldn’t find the specs for the euro 3 and 4 so it’s still fingers crossed and pray

Fingers crossed and pray has been my MO for most of this work so why stop now

 

[WildFeraligatr]

Evening all - I have a bit of an update.

After charging the battery and checking the ECU fuse(s) I tried starting up the car again today. Same issue, same fault code (U1600), same reaction from the immo light (comes on the first time I crank the engine after having cleared the faults, but any time after that it acts as normal).

However, I've now noticed that the power steering light is flashing red inconsistently - sometimes it comes on for half a second or so, and sometimes it comes on for a couple of seconds.

I'm not certain what else this could be at this point because i wouldn't have thought a power steering fault would stop the car from starting, and I'm inclined to believe the ECU is getting power/is grounded correctly because all the other lights are working as normal, and another fault rang up correctly when i forgot to plug the temperature sensor back in. I'm a little lost now as to what I can do next apart from getting someone to test the ECU itself but it seems weird that it's randomly developed a fault at the same time as my having replaced the engine!

 

[koalar]

Voltage at at the oil pressure sensor ?


Same with the third party radio disconnect ?

 

[WildFeraligatr]

Voltage at at the oil pressure sensor ?


Same with the third party radio disconnect ?

Will check when I go back out tomorrow. Where's the oil pressure sensor?

 

[koalar]

Will check when I go back out tomorrow. Where's the oil pressure sensor?

Near the oil filter

 

[WildFeraligatr]

Near the oil filter

Ohh the one next to the crankshaft sensor?

 

[koalar]

Ohh the one next to the crankshaft sensor?

It’s close and only one wire

 

[WildFeraligatr]

It’s close and only one wire

Right, I'll give it a try.

Do I need to have the engine cranking as I test for voltage or is just having the ignition on good enough?

 

[koalar]

Right, I'll give it a try.

Do I need to have the engine cranking as I test for voltage or is just having the ignition on good enough?

Ignition on only

 

[WildFeraligatr]

Ignition on only

Great, is that the same for testing voltage anywhere?

Edit: by anywhere I mean on all the other sensors etc

 

[koalar]

Great, is that the same for testing voltage anywhere?

Edit: by anywhere I mean on all the other sensors etc

Yes should be the 5V reference voltage as used by most sensors

We know there some volts there as the light works properly

Convenient place to measure as it only got one wire

 

[Pugglt Auld Jock]

Yes should be the 5V reference voltage as used by most sensors

We know there some volts there as the light works properly

Convenient place to measure as it only got one wire

Being an "Oldie" it always takes me by surprise when 5 volts pops up on stuff like this when previously it would have been battery volts.

 

[WildFeraligatr]

Here's some voltage updates. For context this is testing the voltage with a multimeter with the +ive lead on the plug and the -ive lead on the battery negative terminal.

Oil pressure plug: 11.1V
Crankshaft sensor: 2 pins, one shows 1.4V and the other shows 2.28V
Camshaft sensor: 3 pins, 4.95V, 4.95V, 0V

For arguments sake I also tested what I believe to be the ECU power supply (pic attached but matches the wiring diagram in Haynes manual) and got 12V.

I am removing the radio now and will post results of my tests shortly however the voltage at the crankshaft sensor seems off to me so thought i should post this now.