Technical Interior light timer

[Finn]

Hi everyone. Tried searching the forum but didn't find the answer yet... The load space light on my 2006 (pre-facelift) Ducato Maxi used to go out after a certain time, even though the doors were left open. This is good, because in the winter I park in my heated garage and open the doors for the night, so my tools dry and compressor oils etc. stay warm. If I wanted to get the lights back on again after the timer turned them off, I would either press the switch inside the load space door, or open one of the cab doors; the timer would then reset, allowing the lights to be on again for the set time. Now, however, they just stay on as long as the doors are open, even for hours.

I have a lot of LEDs in there with their own feed and a relay that takes the signal from the original cargo space light, so if they stay on it's quite a drain on the battery, especially in a cold country like Finland where the battery is in the cold a lot.

Does anyone know where the timer is located and can I do something to it, or replace it?

Additional info, might affect: the load space lights' feed is from an auxiliary battery, which has a cut-off relay that cuts the connection below 10.5 or so volts (i.e. when the main battery dips below that) and connects at something like 13v, so the load on it shouldn't drain the main battery. It used to work normally though, and this aux battery arrangement has been fitted for a good while now.

Any ideas?

Steve

 

[Communicator]

Hi Steve,

I have owned a 2006 x244 from new, however it is a PVC, so no load area light. The cab courtesy light does not have timer, and there is no mention of a timer in eLearn. It is possible that your timing function was performed by an added timer? Another possibility is that the timer is a feature of the Maxi, and is implemented by the "Switch Control Panel", H090 via which the supply to the interior lights, and many others are connected? The switch control panel is located in the dash, behind the four push button switches.

For an easier solution, I am assuming that your relay is controlled via the load area light positive. Would it be possible to modify the circuit so that the relay coil is connected directly across the load area light? All of your load area lighting would then be controlled via the rear courtesy light selector switch. Perhaps that switch is too difficult to reach?

Here is a link to the appropriate section of eLearn. I am also attaching an edited version of the diagram E2510, my wiring colour code chart, and my compiled list of the switch control panel connections/functions.

Please post anything that you discover, so as to assist others.

Alan

 

[Finn]

Hi Steve,

I have owned a 2006 x244 from new, however it is a PVC, so no load area light. The cab courtesy light does not have timer, and there is no mention of a timer in eLearn. It is possible that your timing function was performed by an added timer? Another possibility is that the timer is a feature of the Maxi, and is implemented by the "Switch Control Panel", H090 via which the supply to the interior lights, and many others are connected? The switch control panel is located in the dash, behind the four push button switches.

For an easier solution, I am assuming that your relay is controlled via the load area light positive. Would it be possible to modify the circuit so that the relay coil is connected directly across the load area light? All of your load area lighting would then be controlled via the rear courtesy light selector switch. Perhaps that switch is too difficult to reach?

Here is a link to the appropriate section of eLearn. I am also attaching an edited version of the diagram E2510, my wiring colour code chart, and my compiled list of the switch control panel connections/functions.

Please post anything that you discover, so as to assist others.

Alan

Thanks Alan for your in-depth response and attachments. I haven't had time to get deep into it, but I'm surprised by the apparent lack of timer on the diagrams. Local enquiries suggest that it is a common feature at least here: my friend has a 2003 2.3 (not a Maxi) and his has the timer, and a customer with a Maxi also has it. However, another friend who sold his Maxi a few years back recalled that in his they stayed on indefinitely. Of course it is possible that his had developed this same fault, or that he remembers wrong... A mechanic friend and Fiat fanatic posited that it might be possible there are regional variations, also in the wiring. Could it be that UK vehicles didn't have a timer but Finnish ones did? Seems a strange thing to leave out of one market's vehicles though. Also doesn't strike me as the sort of thing that would have been an optional extra, or could it have been?

I will continue to try and find out what it might be. I also heard that there are, somewhere in the world, inline timers that can be fitted to the feed going to the light, for example. If that's the case that would be an easy fix, although I'd still like to know what broke, why it no longer works like it did!

Steve

 

[Finn]

The only development so far is that it miraculously started working again, no idea why, worked for a few days then changed its mind again! However, when the timer was working again I timed it as I was doing other things in the garage: the timer was 15 minutes on, then they went off. The timer reset and the lights came on again after pressing the courtesy light button of the open door or opening one of the cab doors.

But like I said, it changed its mind and now we're back to the interior lights staying on indefinitely and not switching off. A mystery. Unfortunately (I guess) I'm so busy with work I haven't been able to delve into it in depth, so I'm just leaving the side door open with something wedged against the switch when I leave it in the garage overnight! But there certainly is a timer somewhere, and other owners here in Finland also say theirs does the same, so the questions remain: why is it not visible in the wiring diagram, what controls it and how can it be fixed?

 

[Communicator]

Finn,

I have given your problem some thought, and I am still of the opinon that the timer can only be a feature of the "Switch Control Panel", H090, as it would need to be implemented via some electronics.

(A similar timer feature exists for the load area lights of our other two vehicles, 2001 Saab Estate, and 2013 Skoda Fabia Estate.)

What is required is a 15 minute pulse output timer, which is triggered and reset by the door operated switch.

The Switch Control Panel does many things, some of which are not obvious from the wiring diagrams. Examples are dipped beam headlamps, which will not illuminate if fuse F24 (LH Cab) is faulty. F24 is not shown on the dipped beam wiring diagram. Likewise main beams require F37 to be OK, but it is not shown on the main beam diagram. There is no mention of a timer function in the text relating to diagram E2510, but errors of omission are not uncommon in eLearn.

My conclusion at the moment, is either an intermittent fault in the switch control panel, or in one of the supplies or the earth connection.