Technical Ducato 2.8 2005 lights and fog light issue

[maxfloris]

hi all,

I am experiencing a problem with my dipped lights. They are not working when I turn the switch next to the steering wheel.
Because the lights are not working, also my rear fog lights and instrument lighting is also not working. Which I think make sense if I follow all the electric diagrams from Elearn.

I measured and tested all wiring up untill the Switch Control Unit H090. So I ordered a new one and replaced it but it still didn't fix the problem.

I now created a bypass, I connected the wires from H090D-17 and H090A-8 (which is the same connector btw) and now the lights do work when I use my stalk.
So if I bypass h090 switch control panel, the lights work.

My guess is that one of the other connections towards the switch control panel causes a short circuit or other issue so the control panel is not working properly.

Does anyone have a clue? I could not find any explanation on how the switch control panel works, it is a PCB with some relais and chips.

 

[Communicator]

Hi Max,

I can understand your disappointment and frustration when the new module did not fix the fault. I have a 2006 2.8JTD, and maintain an interest in associated faults.

The switch control module is a "black box", and functions in several different areas.

I am pleased that you have confirmed my suspicion that the module is a mixture of electronics and relays. These would be required for the direction indicators/hazard warning.

As it is unlikely that your new module has the same fault if any, as the old module, I can only make one suggestion at the moment.

As you state the 0V (earth) control signal for the dipped beam enters H090 at D17, and the earth for the dipped beam headlamp relay leaves at A8.

Is it possible that the signal for the relay comes from a different source, and is only controlled by the input from the switch?

I am looking on diagram E2030 FRONT foglamps. There is an earth connection to H090 B10 on that diagram. Just a wild guess, but perhaps worth checking?

Another related thought is that the connector locations are shown for most modules, such as column switch, fuse panels etc, but not for the switch control module. Is it possible that the module was added at a late stage in the development of the x244 model?

 

[maxfloris]

Thank you for the reply.

This weekend I was going in a different direction, I was checking the interior lighting, that was also not working.
I checked the fuse that I did not check yet, namely F24 in B002, see attached file.
That fuse was indeed blown and after replacing it, the interor lighting did indeed work. And also the indication for the city lights also popped up....(that did not work before).

After that I also tried the REAR fog lights....also worked again.

And I removed by dip lights bypass, H090D/17 with H090A/8, put it back in the connector and everything worked as it should again....
Finally I also replaced the H090 control switch panel for my old one (which I thought was broken) and it still worked fine...

So bottomline, the FUSE F24 which protects the interioir lights, is also doing something in the dip lights circuit, see other attached picture. but i could not find the dependence..

And the rear fog lights are depending on the diplights, but from the schematic I could only see a mechanical dependence, namelly the light stalk....

But in the end I managed to fix it, luckily. It all happend because I replaced my fan switch...

 

[Communicator]

Hi Max.

Fuse F24 is also shown on diagram E2030 (Front) Fog Lights (see attached file) which are an option,and not fitted to many Ducato vehicled It connects to the H090 / A2 via D097C/1-4. In general D097 is described as a "short circuit coupling". To me that is a translation problem. a better term would be "linking coupling". Front foglights are an option, and not fitted on many Ducato vehicles.

Perhaps the lesson to be learnt is that with any problems involving H090, it is wise to check all the inputs, including the earths. With your problem in mind I have made a pencil and paper list of all the connections to H090, and designated the connections as either input or output. I am thinking about making my list into a pdf file.

 

[maxfloris]

I am a little bit in doubt now, because it could have also been fuse F37 that I replaced.
Because if you follow F37 from pin 8 through D097 there is some kind of split in H005 with 1 side going to the side lights, see attached city lights figure. In this picture there is also a picture that could indicate the dashboard light of the side lights marking B.

Could that be it?

 

[maxfloris]

In Elearn explanation regarding the side lights it states that this line is protected by fuse F24, see attached.
Same as in my booklet, F24 is for the licenceplate lighting(I did not check that) and parkinglight indication light(same as side lights)

Hm, so if I would have read the service manual that was in my car already, I would not have it trouble shoot this much...oh well, atleast I now know how I can utilize the 2 spare switch on the H090, the frontfog lights and ASR, both I do not have, bu they are just connecting the earthing to certain pins. But that will be a different topic

 

[Communicator]

I am a little bit in doubt now, because it could have also been fuse F37 that I replaced.
Because if you follow F37 from pin 8 through D097 there is some kind of split in H005 with 1 side going to the side lights, see attached city lights figure. In this picture there is also a picture that could indicate the dashboard light of the side lights marking B.

Could that be it?

Max,
I think that you may be confused here. On drawing E2010 Side, tail, & number plate lights, H005 is the column switch. Unfortunately no position marking, but as shown OFF, rotate clockwise = Side etc, rotate further = Headlamps with sidelamps still lit. The picure/sketch at top RHS shows which is connector "B". Incidentally on a marked up print, I have shown an additional connection pin 7 on D097B, but I have not marked where to?

eLearn has many errors. An example is at top LHS of E2010. Fuse rating is given as 10A. Impossible as it is a maxi fuse. Other digrams show 30A.

 

[Communicator]

In Elearn explanation regarding the side lights it states that this line is protected by fuse F24, see attached.
Same as in my booklet, F24 is for the licenceplate lighting(I did not check that) and parkinglight indication light(same as side lights)

Hm, so if I would have read the service manual that was in my car already, I would not have it trouble shoot this much...oh well, atleast I now know how I can utilize the 2 spare switch on the H090, the frontfog lights and ASR, both I do not have, bu they are just connecting the earthing to certain pins. But that will be a different topic

I have used the foglamp positions, wiring, and relay for LED DRLs. I diverted the relay negative to the LHS sidelight via a blocking diode, and added a small 12V to 5V converter in the output wire to power the LEDs. Fuse F09 was derated to 5A.

 

[Communicator]

Max,

I do not wish this thread to drag on, but I have had one of those "light bulb" moments, when I remembered a previous thread relating to the same problem. On that occasion I incorrectly ascribed the cause to a possible difference in the wiring in the engine bay fusebox, in that the positive supply to the headlamp relay was connected to the load side of F24. (On digram E1010 Power Distribution, the supply to both headlamp relay coils is missing, it should be to the supply side of F24, and ignition switch controlled.

I think that you have pointed to the correct cause of the problem.

Operation of dipped headlights requires F24 to be intact.

 

[Timpkellis54]

hi all,

I am experiencing a problem with my dipped lights. They are not working when I turn the switch next to the steering wheel.
Because the lights are not working, also my rear fog lights and instrument lighting is also not working. Which I think make sense if I follow all the electric diagrams from Elearn.

I measured and tested all wiring up untill the Switch Control Unit H090. So I ordered a new one and replaced it but it still didn't fix the problem.

I now created a bypass, I connected the wires from H090D-17 and H090A-8 (which is the same connector btw) and now the lights do work when I use my stalk.
So if I bypass h090 switch control panel, the lights work.

My guess is that one of the other connections towards the switch control panel causes a short circuit or other issue so the control panel is not working properly.

Does anyone have a clue? I could not find any explanation on how the switch control panel works, it is a PCB with some relais and chips.

hi can i ask where you got a new h090? as i fear mine may be on the blink (both hazards and indicators have failed).

 

[Communicator]

hi can i ask where you got a new h090? as i fear mine may be on the blink (both hazards and indicators have failed).

£312.86 on Ebay from Coastal Motorhomes.

Perhaps the attached diagram can help to confirm your diagnosis.