Technical fiat ducato 2007 not charging

[Communicator]

No light comes on, on the panel.

This is suggesting that there is no connection between D+ on the alternator and connector pin A52 on the BCM.

I do not know how the BCM is programmed to respond to no connection with D+, but in the nomal course of events it expects to see about 1K Ohm, and will the send the initial excitation to the alternator. The BCM monitors the D+ wire for the correct voltage, and turns off the warning light when the output reaches the correct value.

From a previous thread, I believe that forum member @koalar has considerable knowledge in this area. Perhaps he may be able to make further suggestions.

 

[AlexGR]

One think to notice is that even though there is no indication coming up on the instrumental panel, there is an error light coming on on the habitation control panel of the motorhome, which indicates that the alternator does not charge the starter battery. I don't think that this panel is connected on the alternator, because it only comes on when the starter battery falls bellow 12V (or something like this).

 

[koalar]

Instead of using jump leads as an earth ,

It's better to do a voltage drop test
Measure the voltage from the battery negative to the engine block while cranking, if you have a bad earth the block will go hot, If not I would be looking elsewhere, it's as simple as that

I have used a test light but you can use a multi meter, it's on either end of what should be a short, so the bulb should not light. This car has a fault

We need to know which wiring to look for
Year, engine, body controlled alternators should output 14.1V, not all Ducato are under BSI control I believe,

 

[jackwhoo]

One think to notice is that even though there is no indication coming up on the instrumental panel, there is an error light coming on on the habitation control panel of the motorhome, which indicates that the alternator does not charge the starter battery. I don't think that this panel is connected on the alternator, because it only comes on when the starter battery falls bellow 12V (or something like this).

at key on I think the battery warning light should come on and then go off to show the charging system should be working.
If the battery light does not come on at all when key turned on but before starter motor operating then indicates a problem.

The fact that the alternator generates a decent voltage when accelerated to it's self excitation speed may show there is a problem with the exciting wiring.

 

[koalar]

We need to take little steps

First we need to confirm the engine block is truly ground

Otherwise the warning lights will not work correctly and any other voltage tests meaningless

The easy way is discribed above

We also need to know which system we are dealing with

Most are controlled by the body computer

But the 2.0 16V just has a bulb in the dash, blown bulb no charge, which is why I asked for the model, engine and year

 

[AlexGR]

Instead of using jump leads as an earth ,

It's better to do a voltage drop test
Measure the voltage from the battery negative to the engine block while cranking, if you have a bad earth the block will go hot, If not I would be looking elsewhere, it's as simple as that

I have used a test light but you can use a multi meter, it's on either end of what should be a short, so the bulb should not light. This car has a fault

View attachment 429432


We need to know which wiring to look for
Year, engine, body controlled alternators should output 14.1V, not all Ducato are under BSI control I believe,

Will do this test and keep you posted. I think I got your point.

at key on I think the battery warning light should come on and then go off to show the charging system should be working.
If the battery light does not come on at all when key turned on but before starter motor operating then indicates a problem.

The fact that the alternator generates a decent voltage when accelerated to it's self excitation speed may show there is a problem with the exciting wiring.

Let me clarify. The battery indication comes on when switching on the ignition switch. However, it comes out and never comes in again after the engine is running. It does not come in again not even before I rev to 2-2.5K rpm, where the issue appears

We need to take little steps

First we need to confirm the engine block is truly ground

Otherwise the warning lights will not work correctly and any other voltage tests meaningless

The easy way is discribed above

We also need to know which system we are dealing with

Most are controlled by the body computer

But the 2.0 16V just has a bulb in the dash, blown bulb no charge, which is why I asked for the model, engine and year


View attachment 429435

It is a Fiat Ducato of late 2013 (facelift), 2.3 Multijet 130. Serial number starts with ZFA250...

 

[jackwhoo]

The battery warning light appears to be working correctly after all.

 

[koalar]

It is a Fiat Ducato of late 2013 (facelift), 2.3 Multijet 130. Serial number starts with ZFA250...

That's great

The D+ is under both ECU and BSI control, you probably have battery monitor and battery cut off switch as well

I can only help you with the D+ and BSI charge control as that's all I have experiance of

It's likely the fault within this circuit, battery, alternator or belt

The first test is check the voltage of the block like in the video while cranking, poor reference ground and the BSI will cut the charge and all other testing is null a void

 

[koalar]

The battery warning light appears to be working correctly after all.

It's confusing as several people with different vehicles and faults are on the same thread, we have to start from the beginning again and confirm each step

 

[AlexGR]

Here's the test as suggested by @koalar.


Did some more tests as following. You may see that after revving up to 2-2.5K rpm the voltage goes to 14+ Volts. In the video I am also showing where the jump cable is connected on the alternator.
Alternator (+) to engine block
Alternator (+) to chassis

I am also sharing here the model of the alternator

 

[koalar]

Here's the test as suggested by @koalar.


Did some more tests as following. You may see that after revving up to 2-2.5K rpm the voltage goes to 14+ Volts. In the video I am also showing where the jump cable is connected on the alternator.
Alternator (+) to engine block
Alternator (+) to chassis

I am also sharing here the model of the alternator

View attachment 429482

That's great

. 5V on one lead isn't great but nothing to worry about a certainly not your problem

Time to move on

Leave it with me for a few minutes

 

[jackwhoo]

Does the voltage output at low rpms change if you turn on a lot of electrical items , head lights, vent fan on maximum .

I wonder if the alternator controller "thinks" the battery is near fully charged so is not "asking" for much power from the alternator . "Smart" alternators confuse a lot of people.

 

[koalar]

We need to check the D+ lead

This controls the charge rate

Starts the charge process (excite the coils)

It's checked at start up, so know it's not broken


On you vehicle is there easy access to the back of the alternator

Is there a brown and green thin cable

 

[AlexGR]

Does the voltage output at low rpms change if you turn on a lot of electrical items , head lights, vent fan on maximum .

I wonder if the alternator controller "thinks" the battery is near fully charged so is not "asking" for much power from the alternator . "Smart" alternators confuse a lot of people.

Yes, the voltage is changing when load is added. The control panel in the video is monitoring the starter battery voltage

We need to check the D+ lead

This controls the charge rate

Starts the charge process (excite the coils)

It's checked at start up, so know it's not broken


On you vehicle is there easy access to the back of the alternator

Is there a brown and green thin cable


View attachment 429502

No, I didn't find any such kind of cable.
Here are some videos of the alternator under and above the engine. Actually I have noticed two things. One, is that I do not see any earth ground on the alternator, while the second one is that I see a plug (not connected anywhere) of which the cover (I guess it's the cover) is decomposed. For the latter, I am not sure if it's just an unused plug or it used to be connected somewhere, but now is not.

Unused alternator plug
Alternator view under the engine
Alternator view above the engine (part1)
Alternator view above the engine (part2)

And another view of the unused alternator plug

As for the starter motor, it definitely needs the earth ground to be replaced.

 

[koalar]

That's great

The broken plug looks like the one that should go here

I will post some pictures here in a moment

There should be two pins one to the ECU and one to the BSI

ECU monitors the load(dfm https://www.google.com/search?q=dfm...d-huawei-rev1&sourceid=chrome-mobile&ie=UTF-8)


The other which monitors and supplies a current to start the charge,


Looks to me as if this is missing and the alternator is charging after you rev the van (self excited)


The earth lead isn't too much of a worry yet I would expect a drop of about 0.2V and you have a drop of 0.5V it should still work and will need doing eventually but let's concentrate on the main problems for now

 

[koalar]

Great thanks for taking the trouble to post the photos

You have part of the wiring harness broken off and left on here

L should be connected the BSI body computer

DFM should be connected the ECU engine computer

The broken connector here

It's very important to locate the broken wire. If they touch the wrong part it would be a very expensive repair


I would disconnect the battery ASAP. And not start the van until its been at least located and isolated


It's never going to work as intended until this is fixed

 

[jackwhoo]

The photo of your starter motor shows the LIVE wire from the solenoid to the motor
DO NOT connect this to the engine block or other ground point!

 

[koalar]

The photo of your starter motor shows the LIVE wire from the solenoid to the motor
DO NOT connect this to the engine block or other ground point!

Correct

We have a ECU wire floating around somewhere

We have a BSI wire floating around somewhere

We have bare high current wires

We have bare pins on the back of the alternator

We don't know how all this happend

But unless it's put right properly It could all end very quickly in tears and turn very expensive

 

[AlexGR]

Great thanks for taking the trouble to post the photos







View attachment 429516
You have part of the wiring harness broken off and left on here



View attachment 429514
L should be connected the BSI body computer

DFM should be connected the ECU engine computer

The broken connector here



View attachment 429518

It's very important to locate the broken wire. If they touch the wrong part it would be a very expensive repair


I would disconnect the battery ASAP. And not start the van until its been at least located and isolated


It's never going to work as intended until this is fixed

It is very weird how this happened. I could only think, when the timing belt was replaced in Germany, before I import the motorhome. Maybe the engineer that replaced the timing belt did something wrong. Or maybe this cable was placed in a spot close to the belts and got cut by them.

Is there any site that we can locate, based on the specific chassis number, the wiring diagram and the related cable?
This will help me also to locate the route of this cable and where it is currently hanging around.

Taking the chance also to thank all of you for your support. Your support is vital in order to avoid shops where they will start replacing everything until the fault is corrected.

The photo of your starter motor shows the LIVE wire from the solenoid to the motor
DO NOT connect this to the engine block or other ground point!

Do you mean, to NOT manually connect those points in scope of any kind of test, right?

Next week I will arrange a visit to electrician engineer to get the job done properly. I don't want to take any risk myself. I will have both grounds replaced (engine to chassis and starter motor ground) and also replace the DFM cable.

 

[koalar]

The starter motor and alternator should not have seperate earths

They are connected to ground via their cases and bolts no wires

This wire should be insulated and carries high current

It should never be connected to anything else