Technical Getting too old for this! How do I wire auxillery high beams?? Ducato 2006 244 2.8JTD

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Technical Getting too old for this! How do I wire auxillery high beams?? Ducato 2006 244 2.8JTD

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Dec 8, 2012
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Hello there fellow Fiat Fanatics.:cool:

I am apperently getting too old to work on my car!
I have been trying to wire my auxillery high beam lights - but fails miserably.

I have always used a normal relay the last 30 od years for this kind of job.
30 - Power from the battery (with a fuse of course)
87 - Consumer (in this case the 2 auxillery lights)
85 - Power in from the fusebox where the High beam fuse is located (in this case F30 in the main box in engine bay)
86 - Ground going to a switch beside the dashboard and then to chassis ground.

Pretty straight forward - I thought.

(In Denmark auxillery lights may only work when the original lights are on (in this case both my main high beams and aux beams should turn of when dipped to normal)

But for some reason the power (from F30 fuse box) is always on, so I can't turn the aux light off automatically without using the mentioned switch
Is there some hidden feature or am I just being daft?
 
Model
2.8 JTD MAXI - former disabled bus
Hello there fellow Fiat Fanatics.:cool:

I am apperently getting too old to work on my car!
I have been trying to wire my auxillery high beam lights - but fails miserably.

I have always used a normal relay the last 30 od years for this kind of job.
30 - Power from the battery (with a fuse of course)
87 - Consumer (in this case the 2 auxillery lights)
85 - Power in from the fusebox where the High beam fuse is located (in this case F30 in the main box in engine bay)
86 - Ground going to a switch beside the dashboard and then to chassis ground.

Pretty straight forward - I thought.

(In Denmark auxillery lights may only work when the original lights are on (in this case both my main high beams and aux beams should turn of when dipped to normal)

But for some reason the power (from F30 fuse box) is always on, so I can't turn the aux light off automatically without using the mentioned switch
Is there some hidden feature or am I just being daft?
You might find that the vehicle is switching earth, and not the +12V. Suggest you use a multimeter and back probe the existing headlights to determine.
 
See photo
You need to find the cable to the light which comes from pin 87. This is where you need your pin 85 connected to.
When high beam is on then your pin 85 on your Aux relay will be positive & your dash switch can send earth to 86 to turn Aux light on
This will make sure you can't turn on Aux lights without high beam being selected.
This is the same rule in Australia.
 

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See photo
You need to find the cable to the light which comes from pin 87. This is where you need your pin 85 connected to.
When high beam is on then your pin 85 on your Aux relay will be positive & your dash switch can send earth to 86 to turn Aux light on
This will make sure you can't turn on Aux lights without high beam being selected.
This is the same rule in Australia.
Cool, thank you very much👍🤩
And I can see you also have those smart fuse holders for inserting in an existing fusebox.
I just discovered those yesterday 🤣🤣🤣🥴🥴
 
Hello there fellow Fiat Fanatics.:cool:

I am apperently getting too old to work on my car!
I have been trying to wire my auxillery high beam lights - but fails miserably.

I have always used a normal relay the last 30 od years for this kind of job.
30 - Power from the battery (with a fuse of course)
87 - Consumer (in this case the 2 auxillery lights)
85 - Power in from the fusebox where the High beam fuse is located (in this case F30 in the main box in engine bay)
86 - Ground going to a switch beside the dashboard and then to chassis ground.

Pretty straight forward - I thought.

(In Denmark auxillery lights may only work when the original lights are on (in this case both my main high beams and aux beams should turn of when dipped to normal)

But for some reason the power (from F30 fuse box) is always on, so I can't turn the aux light off automatically without using the mentioned switch
Is there some hidden feature or am I just being daft?
Getting old? We all suffer from that. Just how old is too old?
It is preferable to have relay coil terminal 86 on the positive, as this ensures the you can use diode equipped relays. Fiat do not adhere to the Bosch convention in this respect, and make either 85, or 86 positive as convenient. They only use relays fitted with a resistor in parallel with the coil.
As you have found F30 is always live. I have attached Main Beam wiring diagram, E2012. If you require more wiring info you could try here and scroll down for links to connector details., but some of the wiring diagrams are unreadable.
 

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  • eLearn E2012 Main Beam.pdf
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