Body Integrated Module and LEDs

[GuerillaZhou]

I cannot edit the title, but it should be Body Integrated Module

Back in December of 2013, I noticed my LED DRL strip on my BRZ stopped working and since I have been swamped with work I did not have time to take it in until now. I just know it's not a fuse problem. So the dealership could not figure out the problem initially and they called Subaru technical support, and Subaru technical support attributed problem with the LED sidemarkers I put in my car. Back in October of 2013 I bought a pair of clear side markers with LED bulbs to replace the yellow ones but I know the DRL still worked from October til December.

I am not really familiar with the Body Integrated Module so I'm not sure how changing the bulbs could blow something. And according to Subaru Technical support, there are multiple cases. Has anyone else experienced this problem?

[DoomsdayJesus]

They're not even on the same circuit. Sounds like hooey to me.

[GuerillaZhou]

I really wish I can edit the title, but after hours of searching I have figured out the problem.

There are two computers in the car, ECU that controls the engine and the "main body ecu" (body integrated unit or BIU) that controls electrical functions. The engine ECU is located in the passenger side behind the glove box while the BIU is right next to the fuse box on the drivers side. So something must have shorted out on the BIU unit related to my LED strip, but from what I can tell everything else works fine.

I will need to replace the BIU unit, the dealership quoted me $750, so I guess I will live without the LED for now. I hope this is helpful for others in the future.

[afishl1]

Does anyone know how to tell if you shorted the biu?

[EZx2]

Originally Posted by GuerillaZhou

I really wish I can edit the title, but after hours of searching I have figured out the problem.

There are two computers in the car, ECU that controls the engine and the "main body ecu" (body integrated unit or BIU) that controls electrical functions. The engine ECU is located in the passenger side behind the glove box while the BIU is right next to the fuse box on the drivers side. So something must have shorted out on the BIU unit related to my LED strip, but from what I can tell everything else works fine.

I will need to replace the BIU unit, the dealership quoted me $750, so I guess I will live without the LED for now. I hope this is helpful for others in the future.

why didn't the do the replacement under warranty?

[GuerillaZhou]

Originally Posted by EZx2

why didn't the do the replacement under warranty?

They blamed the after market LED bulbs for causing the BIU to short. The tech said the car was not designed for LEDs in those places. But they actually didn't know if the BIU shorted or not. They were able to turn the DRL on and off using techstream. They said I need to pay for the replacement and install, and if the DRL still doesn't work then they would continue to figure out what's wrong. I didn't want to take the $700 gamble.

[GuerillaZhou]

Update:

A week ago I found out that my side view mirrors were not adjusting. I replaced Fuse #1 which the side mirrors share with the BIU. And lo and behold, the DRL turned back on! So LEDs did not cause the BIU to short. The fuse was blown, however the DRL fuse was not. It is strange having the BIU still working with a blown fuse.

[EZx2]

Hi, hopefully it will help here
(situation, when opening doors doesn't yield dome lights "ON", - but switch "ON position" does )

Steps to repair:
1. order new a1764 mosfet component.
2. When arrives, take your btu from under wheel (drivers side)- black box, sits inside white plastic with all wires...

3. Open the cover of unit, recognize burned component, replace
4. Install back

Good luck!

[FT-86 SpeedFactory]

Very informative post there. I'm going to try and get a few of these and test it out.

I would imagine there would be a few other components controlled by either this one or another similar one.

If the dome light stops functioning, you will notice that the illuminated key ring still works.

-Chris

[Koa]

Typical dealership service dept BS. glad to see you got it working OP (oldish thread, I know!)

[EZx2]

Originally Posted by FT-86 SpeedFactory

Very informative post there. I'm going to try and get a few of these and test it out.

I would imagine there would be a few other components controlled by either this one or another similar one.

If the dome light stops functioning, you will notice that the illuminated key ring still works.

-Chris

No other components involved in "burned" dome.
This component has 2 fets in, one for dome (you will clearly view half burned, when another side still functioning)

[blown]

anyone else have some other issues from the biu?

[lbroskee]

anybody know where to get the mosfet component?

[phanguy]

Originally Posted by lbroskee

anybody know where to get the mosfet component?

sorry for ULTRA LATE reply, but i dug up this thread to reply to someone else and saw your post. as of my writing my old ebay auction i bought from for the chips won't even load anymore since it's so old. here is the only link i can find to buy these things:

https://www.aliexpress.com/item/Free...7-fc58d82c3822