Technical Ducato ABS/Hill start. U1712-87 & C0034-29

[VanDerErrol]

Hi all, after searching around and not finding anything that matches my problem(s) I've decided to seek your advice before talking to a garage.

Background:
Ducato 2018 Dual EGR (x290?)
OBD2 reader = Topdon Artidiag 500s
Fault codes experienced:

• C0034-29 (Speed Sensor ront Right Fr - signal Signal invalid)
• U1712-87 (Steering Angle sensor on node C CAN - Missing Message)

Dash message ASR/Hill Start unavailable...
I know this will not pass an MOT (now due).

What I've tried to date

• I cleared the codes and they stayed.
• I tested the FR speed sensor and got no voltages on spinning the wheel - I changed the ABS sensor on the FR wheel. (No change, and in retrospect a dumb waste of time)
  • (I will write up a guide to doing this and the problems I encountered, and share, though...)
• I have replaced the engine earth strap, and added a supplementary strap.

I'm thinking that there's a continuity problem on one or more wires now or corrosion somewhere..

So, I'm after guidance on where there may be common points of failure in the wiring, and testing procedures, please.

I think the attached diagramme is relevant?
Red dotted lines indicate what I think is the wiring route.

Many thanks for any help received.

 

[the green vanper]

Hello,

The eLearn diagnostics description for the U1712-87:

The doc is missing for the C0034-29 front right wheel, but there's a diagnosis for the rear right one:

Attached also the ABS eLearn doc so you can adapt this part of diagnosis for the correct wheel.

 

[VanDerErrol]

Hello,

The eLearn diagnostics description for the U1712-87:

View attachment 461648
View attachment 461649

The doc is missing for the C0034-29 front right wheel, but there's a diagnosis for the rear right one:

View attachment 461652
View attachment 461654

Attached also the ABS eLearn doc so you can adapt this part of diagnosis for the correct wheel.

Thanks, I have that document. What I was specifically after was if there were any known areas along the wiring harness that I should check for wear / intermittent shorting?

 

[the green vanper]

No idea. The x250 was know for water ingress into the engine bay. They improved it a little bit in the x290. I've heard / read of cases that water was going down the engine wire loom to the ECU. And sometimes even further to the BCM... So connectors to check here.

In the x250 the earth points and cables loved to rot. The earth point behind the left headlight unit was very problematic. And the engine / gearbox to chassis strap. No idea if it was improved in the x290.

Ah, and it was the case on the classical commercial van bonnet / scuttle tray, so if you have an integrated motorhome, might be different.

 

[VanDerErrol]

No idea. The x250 was know for water ingress into the engine bay. They improved it a little bit in the x290. I've heard / read of cases that water was going down the engine wire loom to the ECU. And sometimes even further to the BCM... So connectors to check here.

In the x250 the earth points and cables loved to rot. The earth point behind the left headlight unit was very problematic. And the engine / gearbox to chassis strap. No idea if it was improved in the x290.

Ah, and it was the case on the classical commercial van bonnet / scuttle tray, so if you have an integrated motorhome, might be different.

Thanks,
There was a load of water sat on top of the engine when I bought the van. I dried it out, WD40'd it all and then made a cover to go over the top out of an old plastic door card.
I have sealed the windscreen area and don't see any problems now. And I clear the drains regularly.
I've replaced the earth strap and added a supplementary one under the N/S arch.

Wondering where the ECU / BCM are - in the engine bay?? Or are they behind the O/S fuse panel inside??

 

[the green vanper]

If you were the one to make all those preventive changes, there might hve been some damage done before. However it's not a 20 years old van

In the classic commercial van cab the BCM is behind the cover, by the drivers's external knee. The cab fusebox is a part of it.

Usually the ECU is in the engine bay. In my non-diesel van it looks more or less like that:

The connector you can see in the center of the photo is one of the ECUs connectors. The thing in the right bottom corner of the photo is the engine bay fusebox, just as a reference to help you locate the parts

 

[VanDerErrol]

If you were the one to make all those preventive changes, there might hve been some damage done before. However it's not a 20 years old van

In the classic commercial van cab the BCM is behind the cover, by the drivers's external knee. The cab fusebox is a part of it.

Usually the ECU is in the engine bay. In my non-diesel van it looks more or less like that:

View attachment 461861

The connector you can see in the center of the photo is one of the ECUs connectors. The thing in the right bottom corner of the photo is the engine bay fusebox, just as a reference to help you locate the parts

Cracking, thanks.