Hi been reading the mail here for some time and have a question My x250 07 Ducato has the battery light on its been on for the last 3500 miles alternator has been removed tested and is in good order with engine running volts at battery 14+ this light was intermittent at first but is permanently on now. I could live with the light on but the leisure battery isn't charging
Any body else had the same problem or could make any suggestions

I suspect the leisure battery is not getting any charge because the D+ signal from the alternator is not as required to operate the split charge system. Does the fridge still work on battery?
The faults are interrelated, when the charging lamp problem is sorted out then the D+ signal problem should also clear. The lamp has 12v supply to it and when the engine is not running an earth connection is provided via the alternator which operates the lamp. When the alternator is running then the earth is replaced by 12v so the lamp has 12v on each side and goes out. The same 12v is the D+ signal which operates the split charge system and fridge, entry step etc.

Today found a broken wire in loom between fuse board and ecu it wasn't to obvious just noticed as it looked like it had been stretched in one place and was checked as it was measuring just a little low but still allowed some current to pass. So thanks to Fiat Forum , Rayc and Gary at Collins motors who found the fault

collinsofprobus.co.uk diesels remapped etc

The step always worked but the auto retract stopped but it's working again now

witzend said:

Today found a broken wire in loom between fuse board and ecu

The step always worked but the auto retract stopped but it's working again now

Click to expand...

was this 1 fault - or 2..??,

glad you've got things working again,

Charlie

Hi there was only one fault battery light on. If you read rayc's post at the bottom he mentions that the d+ signal is reqd to operate the step, fridge & split charge'
(The same 12v is the D+ signal which operates the split charge system and fridge, entry step)So thats why I mentioned the step was working all along but auto retract wasn't but has started again now that battery light fault is corrected

Glad it is fixed. The D+ signal is used on motor homes to operate those systems which depend upon the engine running to operate them. The paralleling of the habitation and cab batteries to enable charging of the habitation battery whilst running, it switches a separate 12v supply to the fridge element which should only be there when engine is running, retraction of the step on start up if fitted and lowering of a satellite dish on start up if fitted. There may be others but they are the main ones.

The cab manufacturer normally leaves a D+ connection for the motor home manufacturer to connect up to, sometimes it can be quite well hidden.

Hi Ray I spoke with A&N caravan services about the Electro bloc controller and during conversation they said that a common fault with the D+ wire was to many devices added to it. I think I only have the auto step as the fridge draws from engine battery when on 12v regardless whether engine running or not so I don't think overloading caused my failure. Last week I had the opportunity of speaking to a mechanic from our local Fiat main dealer who said although not common it was not unusual for this wire to fail not only on Fiats the last one he remembers was a Ford

Crossingkeeper,

is this a similar issue..??

may be helpful..,
Charlie

varesecrazy said:

Crossingkeeper,

is this a similar issue..??

may be helpful..,
Charlie

Click to expand...

It was Tugboat having an issue with his step/fridge; however this thread reminded me that I did also have an problem with Swift's connection to the base vehicle's D wire, it was a 'quality' crimp-type connector that had failed

Crossingkeeper said:

It was Tugboat having an issue with his step/fridge; however this thread reminded me that I did also have an problem with Swift's connection to the base vehicle's D wire, it was a 'quality' crimp-type connector that had failed

Click to expand...

I was on a mobile connection yesterday,
did a SEARCH..but couldn't link the 2 threads, :bang:

hence the punt to the top of the page

so tugboat would see it..,

Charlie