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2009 Forester X Premium
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Discussion Starter · #1 ·
Hi all, Just got an 09 Forester (upgraded from an 03) I'm looking to do the fog light mod like i had with the 03. On with high beams or with just parking lights. I searched on here but couldn't find anything. I remember it was pretty simple on the 03 just change a ground wire. Is there a post on here that i missed?
Thanks!
 

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2007 2.5XT Limited 4EAT
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With the introduction of CAN in 09 the lights may be run through a module as opposed to a simple relay. Anything is possible but may require a bit more work than on your 03. Just theorizing. While you are waiting for someone with experience with this subject to reply, you may want to see if you can locate a wiring diagram for the headlight circuit to see how the system is wired.
 

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2007 Forester Sports XT 4EAT
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@pistoffjstr the fog lights are controlled thru the BIU - Body Integrated Unit. Looks like it would be pretty simple to modify...

@Snow3d agreed, anything is possible if you want to make it happen. :wink:

Below is the SH fog light wiring to get you started! :biggrin:

Bobby...


['07 FSXT MODding Journal] ['03 X MODding Journal]
 

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Discussion Starter · #4 ·
Thanks for the responses! While i know how to read a wiring diagram that one hurts my brain..... Ill have to keep searching or hope someone posts something more helpful. Thanks for the diagram though!
 

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Per Bobby's diagram, it looks super easy to make it work for this model series.

Disconnect the Violet/Yellow wire from the relay coil to the BIU, and connect the relay coil to ground through a switch. This will remove all the 'logic' from the circuitry and put you in command. Do you have a separate switch for the fogs, or is it incorporated into the stalk? If the latter, then get a separate switch, or be prepared to dig deeper into the diagrams.

There might be a few complications regarding the other wires on the switch (if there is one) or on the light that indicates that fogs are on, but in essence this should take care of it. Another thing that might matter is what the story is on the power circuit MB15. I assume that it's probably key-on, but I can't tell from this diagram.
@2.5x_sleeper - And observations from the related SH diagrams?
 

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Oops, MB15 is only low beam.

Two choices: Feed the relay coil from a key-on circuit instead of MB15, or feed it from both MB15 (low) and MB17 (high) with isolation diodes to restrict it to 'lights on' (high or low). It looks as if the BIU can continue to handle the on/off function, so no need to do anything with that wire. I will provide more info on the diodes if desired.
 

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Discussion Starter · #9 ·
Almost seems like more trouble than it's worth! I'll look into it a little more then decide. Thanks for all the information though!
 
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