Need help on door lighting

[phanguy]

Hey guys. As many of us know, the FR-S doesn't have the door step lights. I've been working on getting some wired in and it sure isn't easy, but I do have mostly functional lights! However I ran into an issue and could really use some help by some folks that probably understand electronics better than I do. Basically I was wiring the lights for the door to the dome light. I ordered a set from Diode Dynamics and wired them directly to a dome light that many vendors sell(a grid of surface mount LEDs). I figured out a better way to wire them after the fact... but during the process i let my positive and ground wires touch for just a second by accident and I saw a bit of smoke. Afterwards the dome light doesn't completely shut off. When the door is closed the dome light should be totally off, but it still has some brightness to it(see attached picture). I checked my fuses but everything looks fine. I'd really appreciate any ideas on what I may have screwed up.


It actually isn't as bright in real life as in the picture. It's not as noticeable in the day time so it wouldn't bother me, but it does bother me a good bit at night.

[wrohdejr]

You shorted out something in the BIU. I did the same thing in my brz but with the driver side courtsey light. You will either have to live with it being on all the time or have the BIU replaced. Luckly for me my dealership warranty mine so i didn't have to pay anything. If you can take it back to stock and complain about it and see if toyota will cover it.

[phanguy]

Originally Posted by wrohdejr

You shorted out something in the BIU. I did the same thing in my brz but with the driver side courtsey light. You will either have to live with it being on all the time or have the BIU replaced. Luckly for me my dealership warranty mine so i didn't have to pay anything. If you can take it back to stock and complain about it and see if toyota will cover it.

what the heck is the BIU?

[wrohdejr]

The BIU is the computer brain the controls all the interior lighting and other electrical things.

Starting in the 2007 model year, all Subaru vehicles use the CAN technology.[[ame="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed"]Wikipedia:Citation needed - Wikipedia, the free encyclopedia[/ame]] Typically, two CAN-buses are used on vehicles: a high-speed CAN running at 500 kbit/s for powertrain communication, and a low-speed CAN running at 125 kbit/s for body control functions and instrument panels. A body-integrated unit (BIU) is used between these two networks

[phanguy]

Originally Posted by wrohdejr

The BIU is the computer brain the controls all the interior lighting and other electrical things.

Starting in the 2007 model year, all Subaru vehicles use the CAN technology.[Wikipedia:Citation needed - Wikipedia, the free encyclopedia] Typically, two CAN-buses are used on vehicles: a high-speed CAN running at 500 kbit/s for powertrain communication, and a low-speed CAN running at 125 kbit/s for body control functions and instrument panels. A body-integrated unit (BIU) is used between these two networks

thanks. and i just did a google search and found your previous thread on it. can you tell me where the biu is located? i'm just curious to see. and i don't know if i want to put it back to stock and take it in. wiring the wires was a real bitch. but i may have to... thanks so much for your help on this!

[HRTROB]

Have you tried putting the stock bulb back and checking if it stays lit? Maybe you smoked something in the led circuit, not the BIU?

[phanguy]

Originally Posted by HRTROB

Have you tried putting the stock bulb back and checking if it stays lit? Maybe you smoked something in the led circuit, not the BIU?

i did test the led circuit and a new one and the led circuit is fine when plugged into trunk light.

[wrohdejr]

I couldn't tell you where the BIU is because the dealership did the replacement. Also after the replacement it had to go through a cycle test to make sure everything was running right which took 6 hours. Plus i have the the limited brz which has push button start so it had reprogram the key fobs to the new BIU.

[phanguy]

Originally Posted by wrohdejr

I couldn't tell you where the BIU is because the dealership did the replacement. Also after the replacement it had to go through a cycle test to make sure everything was running right which took 6 hours. Plus i have the the limited brz which has push button start so it had reprogram the key fobs to the new BIU.

how confident are you that they were telling you everything? i only ask because i've been doing some digging. according to the fr-s service manual, the dome light is managed by the ECU. there is no mention of the BIU at all (unless i missed something). so if you got a new ecu then that might make sense why they had to reprogram your fobs. and if that's the same case for me then perfect cause i'm supposed to get a new ecu from the TBS for it anyway. things may be looking up for me. haha.

[wrohdejr]

Remember mine is a limited subaru brz. The fr-s might be different and you don't have push button start!

[phanguy]

Originally Posted by wrohdejr

Remember mine is a limited subaru brz. The fr-s might be different and you don't have push button start!

true, but our parts aren't going to be that different other than the push to start. and even then i believe yours is just a different ecu and more harnesses, not necessarily a whole other additional module especially if it's just to control the lights? but that's okay. i just wanted to see if it felt like they were either holding back information, dumbing it down, or just had wrong information to give you. it happens. i think we'll see what happens when i get my ecu (finally) swapped and i'll report back in case this thread is seen by anyone else.

[sparks]

Here is the wiring for the BRZ dome light. Main Body ECU = BIU

[phanguy]

Originally Posted by sparks

Here is the wiring for the BRZ dome light. Main Body ECU = BIU

so basically. same difference. i was googling around and saw that in other subarus that the biu is a different module completely and that's what i was assuming here. so thanks a LOT.

[sparks]

And here's the location of the BIU