Hi all, I am hoping someone will be kind enough to help me understand whats going on with my 2015 1.6 Diesel Doblo.

While under warranty (with 5k miles on the clock) it developed a problem where all the dashboard lights would flicker, then all the relays would chatter, various error messages would be displayed and it would die and refuse to start. Sometimes total blackout (like the battery had been disconnected), sometimes turning over but no start, sometimes miraculously returned to normal. Th main dealer kept it for a week and was very vague about the cause/solution, but put a new battery on it and mumbled something about a glow plug shorting to earth.

Two years later, out of warranty, the same thing is happening. I have bought a new battery, and really cleaned the battery connections well, but it still has this intermittent tendency to just act as if the power supply is being disconnected. It is not giving any OBD error codes which leads me to suspect the cause is to do with interruption of DC power to the ECU.

When it is running, it goes like a rocket, 50k miles and well serviced.

Could anyone give me an idea where to start with this please, if I have to push it to the main dealer I would at least like to know if they are trying it on with me.

Any help would be really gratefully received !

Hi

As a starting point..

Try a black jumplead : from Battery Negative.. to Engine metalwork

There are failures of the earth cables reported..

Charlie

Hi,

Possibly bad battery -ve lead or its connection to engine/gear box /body.

If lead not expensive consider replacing it.
Or adding an extra lead between the battery negative and body.

Good luck , Please keep us updated.

Jack

UPDATE

Hi Charlie and Jack, many thanks for your helpful responses.

You were both correct, I tried using a jump lead from battery negative to car body and the problem stopped immediately.

There is a stud welded to the bulkhead to the left of the ECU, this appears to be where the ECU gets its main earth from. So I have run a cable between battery negative and the bulkhead earth stud as a temporary repair and it seems to be running well.

The real cause must be an earth cable fault, perhaps intermittently making a good contact and then not (for whatever reason). Any idea why a main cable would fail? Are they of very poor quality? I would love your opinions please.

So for a permanent repair I will need to find a Doblo wiring diagram to identify the various earth cables and repair/replace as necessary.

So once again, can I ask if anyone knows where I can obtain a Doblo 2015 wiring diagram please?

Many thanks

Good job

The Earth cable is of good weight.. but unsealed

Uk weather..and roadsalt get under the
Crimps..and the cable rots internally

Common failure.. I believe I'm getting the 1st 1 for myself..on an 07 punto

There are failures of the earth cables reported..
Charlie

Click to expand...

That is exactly my final solution today, 2021-08-08.
But I am now searching for a electrical manual for my 2003 Doblo 16v, 14000km.

However, Charlie sat for 5 years ago "The End" for my 2 year old Doblow-Terror...

Thank you, Charlie!!

After the last "give-up-and-drive-the-freaking-auiomobile-to-a-new-technician." that costed me £666.- (!!!) But that was as intermittent as before. No proffessional tech there. no.

Now I have a thick, black, cable with contacts XXXL. And a new ODBII software, the French EOBD-Facile. I come back with a report.

varesecrazy said:

Common failure.. I believe I'm getting the 1st 1 for myself..on an 07 punto

Click to expand...

My cable was 'ok' running a 2nd made no difference

The fix was to clean up the short braided cable on the starter