Technical fiat ducato led headlights
- Thread starter nigel c
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Technical fiat ducato led headlights
I believe that the headlights with the led DRL cannot be retrofitted as they are programmed into the vehicle at build. The OEM ones dim when headlights are switched on and are the 'sidelights'. When the light switch is ON without the engine running or ignition on [parking] they are also on dim.
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Flashing at "ignition on" is normally due to the Control unit "testing" the bulbs with short impulses. On normal bulbs, this is not visible, because they are too slow to react. LEDs react faster, so you see the flashing. Normally that should stop after a few seconds, nevertheless, you may still get an error message because the current through the LEDs is too low. (N.B. this is experience from another car, not a Ducato, but it is a fairly standard procedure)
Normally, there is little you can do about this other than completely re-wiring the LED DRLs with a relay that turns on with ignition and off when sidelights are on.
There may be options to re-program the respective control unit, but I have no experience with that.
Normally, there is little you can do about this other than completely re-wiring the LED DRLs with a relay that turns on with ignition and off when sidelights are on.
There may be options to re-program the respective control unit, but I have no experience with that.
hi there can anyone help i have fitted 2018 head lights with led marker
lights on a 2016 fiat ducato and they are ok until i start the engine then they flash on and off
Hi Nigel did you get this sorted.I just bought some and doing the same thing ?
I have also found myself in this situation. Could a resistor not be soldered onto the feed or negative to the drl to combat error codes poping up and keep the computer from severing power to the drl. Also could anyone link me to a wiring diagram for the drl headlight unit??? Thanks
I have This :
Attachments
sounds really good. have you tried that it works?
No, but I've used AlfaOBD to reprogram other features successfully, and similar LED reprogramming functions in the software for Jeep and RAM (US) are reported to work on US based forums.
Sounds good. Can I ask where you are based? So does this mean by changing the logic of the bcm it will retain all the programming features I.e. to dim when the engine starts or is this a quick fix to stop the hyper flash/ warning light. Thanks
Excellent ! That’s super helpful. I’ve got a basic understanding of electrics but do you think I would be right to assume that the two feeds for drl are full power/ dimmed supply’s? Also I’m not 100% sure on the draw of the leds but would go with a 1 ohm resistor would you think this would be enough? Thanks
I have a set of headlights with standard bulb for DRL and then I have a set of headlights with original DRL built in.
I've done a test on how they each work based on connectors overview.
My test of both lamps shows that:
Pin 9:
LED headlight: is power for LED DRL
Non Led headlight: is power for 21w part of T20 bulb.
Pin 4:
LED headlight: is power for dimmed LED DRL - BUT there must be + 12v on Pin 9 at the same time for it to work.
Non Led headlight: is power for 5w part of T20 bulb.
Pin 5:
I can't find any features for this one
It is important that there is ground on Pin 10.
I do not think that the AlfaOBD tester can activate original headlights with LED since the headlight needs more power supplies to illuminate. I think only it can change the parameters of how much power is consumed so that there is no error message.
It is said that some in the US have tried it on a Ram, but the Ram they have in us is before facelift, so they are not even available with LED DRL headlights.
My plan for a solution is:
the car sends out a PWM signal on Pin 9, therefore the LED DRL flashes. I want to cut wire Pin 9 then made a new ignition signal for the headlight, then take the signal that went before the headlight and use it for the fog light, then the fog light bulb will remove the error message.
inside the headlight, a wire with Pin 9 and Pin 4 must be made with a diode so that there will be + 12v on Pin 9 and Pin 4 at the Main beam, but only + 12v on Pin 9 at non light.
hope it makes sense
I've done a test on how they each work based on connectors overview.
My test of both lamps shows that:
Pin 9:
LED headlight: is power for LED DRL
Non Led headlight: is power for 21w part of T20 bulb.
Pin 4:
LED headlight: is power for dimmed LED DRL - BUT there must be + 12v on Pin 9 at the same time for it to work.
Non Led headlight: is power for 5w part of T20 bulb.
Pin 5:
I can't find any features for this one
It is important that there is ground on Pin 10.
I do not think that the AlfaOBD tester can activate original headlights with LED since the headlight needs more power supplies to illuminate. I think only it can change the parameters of how much power is consumed so that there is no error message.
It is said that some in the US have tried it on a Ram, but the Ram they have in us is before facelift, so they are not even available with LED DRL headlights.
My plan for a solution is:
the car sends out a PWM signal on Pin 9, therefore the LED DRL flashes. I want to cut wire Pin 9 then made a new ignition signal for the headlight, then take the signal that went before the headlight and use it for the fog light, then the fog light bulb will remove the error message.
inside the headlight, a wire with Pin 9 and Pin 4 must be made with a diode so that there will be + 12v on Pin 9 and Pin 4 at the Main beam, but only + 12v on Pin 9 at non light.
hope it makes sense
My take on the AlfaOBD approach is that it modifies the body computer programming to the strategy compatible with LED DRLs, in which case the necessary power is delivered to the correct pins and the behaviour of the LED DRLs is consistent with Fiat's implementation (and legislation).
As I say, I haven't tested it and am making an assumption, but commonly various functions and programming strategies are built into the BCM, but only those enabled that are necessary for the factory built vehicle configuration, and often all that is required is the change of a single byte in the proxi configuration file to enable or disable a particular feature. Fiat dealers don't have the software to do this and the official Fiat approach is that a new body computer has to be ordered, correctly programmed for LED DRL headlamps.
But I have programmed a 2 hour off delay in my uConnect VP2 radio by this method, as well as reconfiguring the number of speakers and balance/fade control, using AlfaOBD. The software function rewrites the BCM configuration file and you then carry out a proxi alignment to distribute the new configuration to the relevant nodes on the vehicle.
Similarly on my Volvo, a cruise control switch costs £60 from a Volvo dealer, plus around £400 charge to install the software to enable it. But the routine is already present in the body computer (CEM) and the "software update" is just a change to a single byte in the configuration file that was easily done with some aftermarket diagnostic software.
Similarly I changed the stop/start system default strategy, which Volvo say cannot be done, and installed a TFT instrument cluster in place of the analogue version - cost me less than £200, Volvo want nearly £1000 for the cluster change
As I say, I haven't tested it and am making an assumption, but commonly various functions and programming strategies are built into the BCM, but only those enabled that are necessary for the factory built vehicle configuration, and often all that is required is the change of a single byte in the proxi configuration file to enable or disable a particular feature. Fiat dealers don't have the software to do this and the official Fiat approach is that a new body computer has to be ordered, correctly programmed for LED DRL headlamps.
But I have programmed a 2 hour off delay in my uConnect VP2 radio by this method, as well as reconfiguring the number of speakers and balance/fade control, using AlfaOBD. The software function rewrites the BCM configuration file and you then carry out a proxi alignment to distribute the new configuration to the relevant nodes on the vehicle.
Similarly on my Volvo, a cruise control switch costs £60 from a Volvo dealer, plus around £400 charge to install the software to enable it. But the routine is already present in the body computer (CEM) and the "software update" is just a change to a single byte in the configuration file that was easily done with some aftermarket diagnostic software.
Similarly I changed the stop/start system default strategy, which Volvo say cannot be done, and installed a TFT instrument cluster in place of the analogue version - cost me less than £200, Volvo want nearly £1000 for the cluster change
Just to add to my previous post, you are assuming I was referring to the Ram Promaster (Ducato) but I meant that people have successfully installed the newer LED headlamp units on non-LED equipped Dodge Ram pickups after reprogramming with AlfaOBD.
yes this is the Ram Promaster:
https://www.ramtrucks.com/ram-promaster.html
this is the old ducato non facelift:
https://www.mascus.dk/transport/varevogne/fiat-ducato-ch-cb-maxi-35-2-3mjt-largo/7q6gafeh.html
this is the new facelift ducato (2014-2020)
https://altomvarebiler.dk/fiat-giver-ducato-den-store-tur-faar-kaempe-facelift/
On the facelift model it is possible to get it with integrated LED DRL in the headlight like thes:
http://bunkervan.es/urban-ducato-l1h2/faro_622x320/
so it is not just a bulb that has been replaced but a headlamp with LED integrated
https://www.ramtrucks.com/ram-promaster.html
this is the old ducato non facelift:
https://www.mascus.dk/transport/varevogne/fiat-ducato-ch-cb-maxi-35-2-3mjt-largo/7q6gafeh.html
this is the new facelift ducato (2014-2020)
https://altomvarebiler.dk/fiat-giver-ducato-den-store-tur-faar-kaempe-facelift/
On the facelift model it is possible to get it with integrated LED DRL in the headlight like thes:
http://bunkervan.es/urban-ducato-l1h2/faro_622x320/
so it is not just a bulb that has been replaced but a headlamp with LED integrated
<Sigh> I know all of that and I wasn't referring to the Ram Promaster, but to the Ram pickup, a completely different vehicle also built by FCA and on which some of the current generation vehicles have LED lamp units. People have replaced their non-LED units with the LED units after reprogramming the body computer with AlfaOBD to tell the vehicle that the LED version lamps are fitted and adjust its operating logic accordingly.
The LED DRL enable function for the Ducato in AlfaOBD is a body computer reprogramming operation, and I believe it works as I have described above. When the programming logic has been changed, the body computer will drive the LED DRLs in exactly the same way as if they had been fitted during manufacture. The BCM operates the non-LED DRLs differently, that is why there are different pins on the headlamp connectors and why reprogramming the BCM should enable the correct current to the required connectors.
But it's your choice. Believe me or not, you could always ask the AlfaOBD developer, he's quite approachable. Or just try it and if it doesn't work then change it back again,
