I have an Ace Napoli motorhome from Swift based on a Ducato 35 100 multijet registered 2007.

The front offside sidelight, rear offside tail light and rear offside (high) marker light are not working. The front nearside sidelight, front (high) nearside and offside marker lights, rear nearside tail light and rear nearside (high) marker light are all working.

The Swift wiring diagrams show the nearside and offside side and tail lights on separate circuits and I cannot find anything in common with the three faulty lights from diagrams. I have checked the bulbs and all fuses (engine bay, under dash and motorhome fuse box) with a meter and all are ok.

Immediately prior to this fault I had to replace the rear offside stop/tail bulb because the stop light blew. Had to do the same back in May. I have also tried several new bulbs even though they show ok on a meter.

I would appreciate any advice on what could be causing this problem. Are there any connectors or other fuse boxes?

Many thanks
Ken

I'm no expert, but sounds as though there could be an earth fault somewhere?

Many thanks for the reply Sean. My thoughts too but I have checked the earth on the rear light cluster which is common to the tail, stop and indicator lights and it's only the tail light that has the fault. Also checked the earth on the front side light and that is ok.

Ken,

Have you spoken to Swift? It could be that there is another fuse board located elsewhere. I am sure that you must have tried for power at the lamp connections?? easy to forget the obvious if not all I could suggest is to back track along the wires until you find a break in power.
Sorry I cant be more specific.
Regards
Stewart

Just had a look at Swifts site (lots of handbooks) not sure which is yours but could only find 1 mention of external light fuses and that stated 1 fuse for front and 1 for rear which does not look to be your scenario.
Stewart

Hi Stewart, Thanks for your investigation and reply. I tried connecting a separate wire from chassis (neg) to the rear offside light cluster ground but that made no difference. I then disconnected the positive from the nearside and offside tail lights and fed the nearside (working one) to the offside (non-working one) and still the offside did not work. Put everyhting back and to my surprise all three non-working ones came on!! Then found that the offside stop light wasn't working. Wiggled the bulb and it came on. Eased the two pos pads out a little and now it doesn't go out when wiggled. The way the bulbs fit in these clusters seems a bit dodgy but that doesn't explain why I lost three lights. Have read that the Body Control Unit can sense problems in a circuit and shuts it down but my Swift circuit diagrams say nearside and offside lights are on different circuits, so again doesn't seem to fit with having three of the four offside side, tail and markers lights failing. All very puzzling.

Ken

You could always ask your question here which is monitored by Swift.

http://www.swift-talk.co.uk/

The factory is closed for a few weeks so you will have to wait for an answer.

Hi Ken,
Pleased you got it sorted, it could be some sort of fail safe system one out all out!!!

I have heard of some of the Fiat's with bulb warning systems to behave in a similar manner.

It does sould like a bad/dirty connection, Ambersil + is recomended by Swift and others.

Regards
Stewart

Did you ever get this sorted. I have va similar problem with no cause! In my case it simply corrects itself sometimes it can be cured by switching on and off. I keep thinking relays but cant find one?