D+ Source on 2018 Fiat Ducato Based Adria Twin

[Alesupper]

Hi All, I have no voltage on my D+ cable going into my EBL208S. Does anyone know where this is fed from and also the location of the fuse? This is on a 2018 Fiat Ducato based Adria Twin. Please see attached photos. I presume that this is the D+ relay because the green wire goes to the D+ input on the EBL208S (pin 16). TIA.

 

[NicM]

The d+ will only work with engine running, have you tried that?

 

[Alesupper]

The d+ will only work with engine running, have you tried that?

Yes engine is running

 

[NicM]

hopefully someone will know more about it on here then.

 

[mitzimad]

i belive fiat supply them for conversion with a plug in the drivers side door pillar and convertors get the d plus signal from that

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[Alesupper]

I have found the attached document from another thread (https://www.motorhomefun.co.uk/forum/threads/ducato-x290-wiring.188788/) on this forum and it suggests that Pin 13 on the 15 pin connector located in the RH side B-Post is the D+ feed. The attached document suggests that this is on a 5A fuse. I Have looked through the dashboard fuse box and found a 5A fuse that is blown, so hopefully this is the source of the problem. Unfortunately I don't have any spare 5A mini blade fuses so I will get one tomorrow and try it out. I will report back.

 

[andy63]

Hi All, I have no voltage on my D+ cable

Hi..
The d+ as we refer to it does not necessarily have to have a voltage present..
On a ford transit I had the d+ provided for the converter was a ground switching signal...
You could use this to power a relay coil..which in turn could then provide a 12 volt feed to power circuts which were required to be engine run actuated..
Hope I've explained that OK.
Andy

 

[NicM]

Hi..
The d+ as we refer to it does not necessarily have to have a voltage present..
On a ford transit I had the d+ provided for the converter was a ground switching signal...
You could use this to power a relay coil..which in turn could then provide a 12 volt feed to power circuts which were required to be engine run actuated..
Hope I've explained that OK.
Andy

If you look at the wiring diagram look like the D1 input is +12Vs.

 

[andy63]

If you look at the wiring diagram look like the D1 input is +12Vs.

Sorry.. just jumped in without reading through the thread..

 

[autorouter]

it suggests that Pin 13 on the 15 pin connector located in the RH side B-Post is the D+ feed.

It says it's the ignition. Maybe they are being inaccurate and it really is the D+, but best to check, it's important for the split charge relay trigger (Pin 16 of the EBL).

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[andy63]

If you look at the wiring diagram look like the D1 input is +12Vs.

Quick look at the wiring dig..
But wherever the d+ positive 12v feed comes from to the hab power supply it will still originate from the base vehicle wiring.. and if that fails then the 12v d+ signal to the hab side fails as well..

 

[Alesupper]

Hi Andy

You have explained that perfectly thank you. Very helpful.

Alesupper

Hi..
The d+ as we refer to it does not necessarily have to have a voltage present..
On a ford transit I had the d+ provided for the converter was a ground switching signal...
You could use this to power a relay coil..which in turn could then provide a 12 volt feed to power circuts which were required to be engine run actuated..
Hope I've explained that OK.
Andy

 

[Alesupper]

Hi All, I am please and relieved to tell you that the problem was a blown fuse. The fuse in question was a 5A fuse located in the dashboard fuse panel. This fuse must supply 12v to the D+ Relay and that is why the EBL didn't kick in when the engine was started. I think that this fuse has been blown since before we have owned this van because the outside step now automatically retracts when I start the engine. This has never happened since we have owned the van. So basically our leisure battery has never been getting charged whilst the engine is running. I hadn't really noticed this because we have 2 x 120W solar panels which keep the battery topped up. I only noticed it now because the new LiFePO4 battery has a bluetooth BMS and I could see that zero current was going to the battery when the engine was running.
In case people are wondering, the EBL on our van supplies 13-14 amps to the leisure battery, so I am going to see how I get on without a B2B for now, especially because we have solar.
Thanks for your help everyone.

 

[Smudger55]

This thread helped me resolve our fridge and rear view not working from engine. Gas would also not turn on without EHU.

Talk of D+ made me look elsewhere as the fuses in the dashboard panel we all ok.

Stupidly i had not looked at Sargent PSU unit where there were to 15 fuses, at 13. One was blwn but both related to the fridge and camera.

Phew, think we csn now carry on up to Scotland.

 

[Jim Schush]

Hi All, I am please and relieved to tell you that the problem was a blown fuse. The fuse in question was a 5A fuse located in the dashboard fuse panel. This fuse must supply 12v to the D+ Relay and that is why the EBL didn't kick in when the engine was started. I think that this fuse has been blown since before we have owned this van because the outside step now automatically retracts when I start the engine. This has never happened since we have owned the van. So basically our leisure battery has never been getting charged whilst the engine is running. I hadn't really noticed this because we have 2 x 120W solar panels which keep the battery topped up. I only noticed it now because the new LiFePO4 battery has a bluetooth BMS and I could see that zero current was going to the battery when the engine was running.
In case people are wondering, the EBL on our van supplies 13-14 amps to the leisure battery, so I am going to see how I get on without a B2B for now, especially because we have solar.
Thanks for your help everyone.

We are having a similar issue with our fridge not working on 12v while driving and also the cab battery meter not working. Both faults occurred as we came off the ferry last week.
I have checked the fridges pcb board and that’s ok, I have checked the fuses on the battery and the electrblok and all are good. I will have a look for the 5 amp fuse later today, fingers crossed.

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[GeoffnDee]

Jim Schush , have you checked the starter battery power input connection on the rear of your EBL unit to confirm a supply is present.

 

[Jim Schush]

Jim Schush , have you checked the starter battery power input connection on the rear of your EBL unit to confirm a supply is present

 

[Jim Schush]

I thought I had, but I now realise the engine wasn’t running. I need to have a look at it again today. Thanks for your advice.

 

[GeoffnDee]

You should find a 12v supply reading at the starter battery input connection on the rear of the EBL with or without the engine running.

 

[autorouter]

I have checked the fridges pcb board and that’s ok, I have checked the fuses on the battery and the electrblok and all are good

Did you check the 20A fuse near the starter battery? That's the one that supplies the fridge on 12V, and also the cab battery meter on the control panel. There should be 3 fuses, a big 50A fuse, a small 2A or 5A for the D+ supply, and a 20A fuse for the fridge 12V heater element supply.

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[Jim Schush]

Did you check the 20A fuse near the starter battery? That's the one that supplies the fridge on 12V, and also the cab battery meter on the control panel. There should be 3 fuses, a big 50A fuse, a small 2A or 5A for the D+ supply, and a 20A fuse for the fridge 12V heater element supply.

I went up again and checked everything again and all fuses ok.
Had a closer look at the EBL unit and on removing block 2 connector which feeds the battery monitor and the 12v D+ fridge I found scorch marks on the first connector (see attached photos).
The connector broke off whilst I was inspecting it.
So I need to find a replacement lok n Mate connector and I have contacted a repairer to see what they suggest about repairing the Ebl.

 

[autorouter]

That pin carries the power for the fridge 12V heater element, while the engine is running. On mine it's 14.4A, which is very near the 15A limit of the pin. If it's not absolutely 100% perfect then a slight resistance develops. That causes heat, which causes further degradation and further increased resistance. The eventual result is what you see here.

I usually get Mate'N'Lok connectors from 12VoltPlanet, but they don't seem to have the 5-way one. It's available from CPC, but a minimum quantity of 5. That's only the plastic connector shell, you also need to buy the pins, which crimp on the wire then slide into the shell until it clicks locked.

https://cpc.farnell.com/amp-te-connectivity/350809-1/plug-housing-mate-n-lok-5-way/dp/CN17831

 

[Jim Schush]

That pin carries the power for the fridge 12V heater element, while the engine is running. On mine it's 14.4A, which is very near the 15A limit of the pin. If it's not absolutely 100% perfect then a slight resistance develops. That causes heat, which causes further degradation and further increased resistance. The eventual result is what you see here.

I usually get Mate'N'Lok connectors from 12VoltPlanet, but they don't seem to have the 5-way one. It's available from CPC, but a minimum quantity of 5. That's only the plastic connector shell, you also need to buy the pins, which crimp on the wire then slide into the shell until it clicks locked.

https://cpc.farnell.com/amp-te-connectivity/350809-1/plug-housing-mate-n-lok-5-way/dp/CN17831

Thanks for your help, I am going to send the unit to A & N for repair when we get back from our next trip. Every days a learning day when you have a motorhome.

 

[Jim Schush]

I contacted A & N and explained that in addition to the fridge not working on 12v, the 12v cab battery was not registering any voltage on the Lt display. Like your suggestion above he advised me to check the 20a fuse near the starter battery.
I’ve just been up and checked all the fuses I can using the continuity setting on the multimeter and they are all ok.
The vehicle is a 2018 Dethleffs and before I remove the Ebl, I am thinking of getting a mobile technician round to check I have not missed anything.
I had a fridge related problem in 2022 and I was advised to send the Ebl away for repair and when it was returned with no faults it turned out some external connectors at the side of the Ebl had melted so needed replacing.
Last year the fridge failed and that was the PCB board.
The coincidence on these similar faults is on each occasion they have occurred within a day or so of returning from Europe after we get off the ferry.
I’m still scratching my but I’m sure with time and possibly money I will get to the bottom of it.

 

[GeoffnDee]

Have you confirmed that 12v is getting to the EBL main connection on the rear of the unit from the starter battery , in case there is a supply wiring fault after the fuses at the starter battery.