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Fog lights on with high beams?

theblet

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Yes exactly. All I am able to find are the fuse diagrams.no info on the relay positions or anything.
 

brian42

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My last truck was like that (2003 Ford). All you had to do was splice in a wire to bypass the relay and, viola, high beams and fogs.

I'm not sure how the wiring goes but many relays are now electronic instead of mechanical and are "triggered" by the signal (voltage/current) in the computer vice the signal through a wire. The BCM contains the setting for the relay (boolean expression, gate logic, or whatever you want to call it). By changing that you change the relay/gate logic to have the high beams AND fogs instead of the high beams OR fogs.

As for accomplishing this via wiring modification I'm not sure if it can be done. Instead of wiring and components for each functions, many functions are now on chips inside group computers (BCM, TCM, ECM, etc.) with wires in and wires out.
 

Jimmy07

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the bcm should not send power directly to the fog lights it should trigger a relay or something to handle the higher current. my gmc sierra had this set up & once you find the hi beam relay & foglight relay you can put a jumper in their but i used a small resistor to prevent feed back to the hibeam relay. i know exactly what you are asking & i have not had time to investigate it yet my truck is only 2 weeks old
On Ram trucks, the BCM DOES supply power directly to all lighting circuits. The BCM is fed with 4 fused battery power wires, and then distributes all body function power. Everything is internal to the BCM. The only way to get the fogs to stay on with high beams AND still use the factory fog lamp switch, is to configure the BCM as such using software, such as AlfaOBD, tazer, Jscan, etc.
 

585nik585

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Спасибо за помощь. Я, наверное, не буду платить 300 долларов только за то, чтобы противотуманные фары оставались включенными. Может быть, если позже я надену шины побольше.

Как вы думаете, дилер может его запрограммировать? Просто подумал, есть ли это в магазине по другой причине.
all that is needed
and Alfa OBD. 15 minutes
 

Jaywoo

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Using AlfaOBD you would go to the CBC Features section of your BCM and change this setting:

Front Fog Lamp Dropout Enabled: Yes

Change the Yes to No and your fogs stay on with your high beams.

I have done that but only use the high beams/fog lights combo off-roading.

As mtehonica said this is not legal on public roads so no dealer is going to change that for you (or any other BCM setting for that matter). Your truck comes with a specific setup for each computer that is either specific to the vehicle model or specific to your VIN. If the dealership changes anything then they would have to update that with FCA (if they can). Then they would be on the hook for it if something happened (caused an issue or you get a ticket) and I'm sure they don't want that liability.
Did you need a security bypass to get into the BCM? I can get to that setting but it won't make the change. Thanks!
 

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