Electrical Issue
 

I have a 2015 Subaru BRZ and I currently installed my HKS supercharger. Just so happens after install my climate control, VSC buttons, window buttons, trunk button, wont come on. I checked fuses, but none seem to be blown. I was wondering if maybe I nudged something while installing the supercharger or just missed plugging something up. I checked all grounds also. The gauge cluster, start button and dome light come one just fine. Just wonder if anyone had this problem or if there is something I’m missing. Please help if you can.

UPDATE.. I found out that I don’t have a fuse issue, but yet an issue with getting power to some of the fuses ( the circuit is not turned on) ..where do I start?

Did you check the interior fuse box?

Yes but not getting power to some of the fuses ..mainly the ones that are causing me the problems

You're going to need this and find whats common between those that are not working:

http://www.ft86club.com/files/BRZwiringi.pdf

Logically in my brain I would think a relay is stuck or a wiring harness got partially crushed or cut somewhere

The troubleshooting section is particularly useful on page 12

and also look at page 378, before most of the fuses, they go way back to an 80 amp and 140 amp fusible link, and even after those on page 380 there's a 7.5 amp ECU-B fuse that can also effect the systems you mentioned aren't working in the engine bay...

At this point I have changed all fuses, and have to trace the wiring harness to look for damage or loose connections. Not sure how to check and see if I have a bad relay

I assume you're using a multi meter. The multi-meter should read 0 ohms between the contacts:

https://www.wikihow.com/images/thumb...-Version-2.jpg

Take a look at the wiring PDF on page 380. looks like most of the components you're having issue with are fed by the 7.5 amp fuse ECU-B. Now go to page 378 and you'll see that fuse is fed by a 30 amp fuse DCC which is fed by the 80 amp main fuse on the battery block. Work backwards with a meter and check for voltage.

UPDATE: I have checked all relays supposing that I was checking them correctly at 20 ohms. (Correct me if I’m wrong). I checked all fuses in the engine bay which all seem to work besides the headlight ones and the windshield wiper ones (a total of six). But get this ...when i connect the battery none of them work..which leads me to believe that’s a relay problem. Also I checked the fuses again inside the car under the driver side dash and all seem to work except for the heater ones and the ones that control the traction button and trunk button. (A total of six). I just want to make sure I am checking the relays properly..if anyone has any input on that it would be greatly appreciated.

[ame]https://www.youtube.com/watch?v=ire7vyDqelg[/ame]

When you say they "all seem to work besides"...stop there and troubleshoot that specifically. How are you checking them? You should be connecting the black lead from your meter to ground and using the red lead to touch the little silver square on top of the fuse (while it's still installed in the fuse box) next to the fuse rating number. You should see 12vdc on both sides of the fuse with the vehicle running or ignition in the correct position to give power to those systems. If you see 12vdc on one side (supply side) but not the other... that fuse is blown. If you don't see 12vdc on either side, figure out what the fuse/connector upstream (using the wiring diagram) that feeds those that have no supply voltage and check for voltage there.

Don't forget that the 12vdc side is only half the circuit, you still have returns and the systems that are not working may share a common connector.

As for relays, they are typically specific to 1 system only and won't affect other systems. Follow the video above if you really want to test them, but I see no reason to look at relays. Cool thing about relays is that a lot of them are interchangeable so if you suspect a bad one, swap it with a another from a system that is working.

I used a test light to test the fuses, but now I am going back out to use the multimeter and check where the issue is coming from by using the diagram. Since I happened to check all the relays they are working just fine.

You've confirmed that you are not getting power to some of the fuses necessary. Have you traced that power back to the source? If it ends in a relay and the relay is functioning, then the signal to trigger the relay is likely not there.

So how do I solve the issue when the signal to trigger the relay is no there? I have also switched out the 80a fuse which most or all of the fuses that are not getting power link to and still nothing. What else can I check?

You have to track that back to its original source. Then sort out why that is not giving up 12V.

Let's pick one element that is not working. Something that is limited in the controls. You said the window buttons don't work, correct? Where does power appear/disappear in the chain from the battery? IE - battery --> 80A --> 30A --> ECU-B/Dome light --> G/R wire --> Main Body CU --> Window Regulator master <--> Window switch --> window motor.

Did you blow up your body CU? :paddle: