Hello all, thank you very kindly for reading my post.

Fiat Ducato 2.3jtd 2005 swift motorhome.

Ok..I have lost my headlights dipped beam and fogs....but the funny thing is they come on again after 5 mins driving! Then if I switch the engine off I lose them again..then drive for 5 minutes then they come back on.

I sort of got used to this, but just recently they went altogether and now I have no front dipped headlights and no rear fogs!!

Obviously I have checked all bulbs, fuses, all the relays that I can find associated with the lights, block connectors, and multi-metered the feeds to the light cluster (nothing reading).

Several months ago I retro fitted a reverse camera, I am wondering if it is this wiring that has mucked up things.

I was told by a friend that I should replace the light switch stalk, but this is expensive and would like to check other possible causes first.

Please please I am at my wits end. Could it be a faulty earth, would a faulty headlight switch stalk effect the fogs as well (switch is on the dash)?

Many many thanks Tim.

Hi mightyworthit. I can't say exactly what your problem is, but can maybe get you a bit further. The dipped headlights work like this: The column stalk control H005 has a 4 position switch with 4 different resistance values. This sends one of 4 voltages to the body computer, which can then sense the voltage to work out what position the stalk is in. This seemingly oddball arrangement is simply in order to use only one wire rather than many. If dip beam is selected, the body computer sends a switching signal to a Relay in the B002 junction box under the dash, and the contacts of this relay close and supply the larger current to both dipped headlights via a separate fuse for left and right. The rear foglights are only allowed on when the dashboard switch is on AND the dipped headlights are on. If you turn on main beam then it figures that it ain't foggy so the rear fogs go out ! The fact that you sometimes lose both dip beams and both rear fogs suggests to me that the common factor is an absence of a dipped headlight signal to the body computer calling for dipped beam. Take a look at the connections from the stalk. I fear that once you have eliminated the obvious things then its a trip to a dealer. I doubt if your reverse camera wiring has any bearing on this fault.

Hi Anthony, thanks for your brilliant reply.

You say to take a look at the connections from the stalk. I guess I am looking for the single wire to the body computer. What is the best way to single this wire out from the many underneath? Once I find it i just need to check that I have/have not got a positive feed when dipped beam is selected. If I buy a 12v light bulb tester it will make things alot easier.

I have a multimeter but this is large and has crap terminals.

Many thanks Tim

Hi Tim. My reply above was based on the assumption that you have an early third generation (X250) model Ducato, which is the one I am familiar with and have the wiring diagrams for. However now I'm beginning to wonder if 2005 means it is one of the earlier second generation type. One of the problems of model names being kept going. If so my apologies, what I said will still be roughly true, but I don't know if your model used a body computer or a traditional switch and relay system. The principle of the rear fogs and the dipped beams being linked is still true. A multimeter is a useful tool, but you may need to get some thin insulated hookup wire to link it in to the circuits you are trying to test. You may also need to source a wiring diagram which will tell you the wire colours etc. Try looking for a workshop manual CD on ebay for about a tenner.

Anthony thanks for the reply again,
Yes sorry I should have said that it is a second generation type not a x250.

I will try and google/ acquire a wiring diagram. Good place to start.

Perhaps I will ask on this forum if any of the other posters have one.

Is a hook up wire similar to a 12v bulb tester with a sharp prong terminal on

You can download the 'elearn' disk here uit has all the diagrams:
https://www.fiatforum.com/downloads.php?do=download&downloadid=439

How did you check the relays, a relay with burned contact may still measure 12v but with a load pass very little current.
.
re: hookup wire
The multimeter probe is too fat to fit into connectors etc soa length of thin single core wire is useful for hooking up to those. You can often fit it in the back of ther connector so no need to disconnect at all.

Thanks for the reply its very kind of you.

Corcai..yes yes yes I located this wiring diagram after digging around the Ducato forum and downloading the eLearn workshop manual.
I then dug around further to get the translation of the wire colour codes. (h is grey apparently!)

I am waiting on my 12v bulb tester to be delivered (£4 from amazon) which should then hopefully allow me to test me the stalk switch.... checking live in and switch live out...as indicated on the wiring diagram.

Corcai, I am probably wrong here, but i am hoping my 12v bulb tester , which has a very sharp prong on will allow me to test 'through' the wire directly rather than having to find connectors...is this correct/bad practice?

Hopefully i will not have to take the steering wheel off to do this

I am hoping that it is the stalk switch hub thingy. There are replacements on ebay for £35.

I replaced similar on my peugeot earlier in the year, not due to a fault but to upgrade my trip computer functionality (it worked!)

IF it isnt this I will methodically work my way through the fault diagnosis flow chart also provided in my Elearn workshop manual.

Any comments???

mightyworthit said:

Thanks for the reply its very kind of you.

Corcai..yes yes yes I located this wiring diagram after digging around the Ducato forum and downloading the eLearn workshop manual.
I then dug around further to get the translation of the wire colour codes. (h is grey apparently!)

I am waiting on my 12v bulb tester to be delivered (£4 from amazon) which should then hopefully allow me to test me the stalk switch.... checking live in and switch live out...as indicated on the wiring diagram.

Corcai, I am probably wrong here, but i am hoping my 12v bulb tester , which has a very sharp prong on will allow me to test 'through' the wire directly rather than having to find connectors...is this correct/bad practice?

Hopefully i will not have to take the steering wheel off to do this

I am hoping that it is the stalk switch hub thingy. There are replacements on ebay for £35.

I replaced similar on my peugeot earlier in the year, not due to a fault but to upgrade my trip computer functionality (it worked!)

IF it isnt this I will methodically work my way through the fault diagnosis flow chart also provided in my Elearn workshop manual.

Any comments???

Click to expand...

You don't need to take off the steeling wheel just take the shroud off its only two torx screws as far as I can remember.

Print off the diagrams for main, dip and fogs. Check whats in common with the dip and fog circuits as they both fault and rule out whats in common with the main dip beam as thats working.

To be honest the first thing I would do is clean the contacts on the stalk unit and H009 unit under the radio.

I am guessing that I can dismantle the stalk in situ, without taking the steering wheel off. Does the end just pop off?

The van is in storage a few miles down the road, so a little tricky for me to experiment.

Thanks corcai.