Pushed start.. didnt start

[im_topher]

Originally Posted by Gords_zenith

Check the AT 7.5 amp fuse near the top right of the diagram, could have something to do with the computer I detect it's in park or neutral to start.

Checked that, its all good, i did a once over on every fuse in the car, they are all good.

[im_topher]

Originally Posted by stugray

In my business the first thing to do is make a list of all the things that need to be true for the "system to reach a desired state" (starter cranks).

Then verify (dont assume) that each of these things are true and that it is being reported as true to the ECU.
This would usually require probing the signals that the ECU sees while exercising every option.

At work we have a Break Out Box (BOB) for every type of connector on every box in the system, so doing this kind of test is trivial.

For us hobbyists, probing every signal in the ECU connector while leaving it connected is difficult.
The pros would use a "Insulation displacement probe" which is a fancy way of saying "poke the DMM probe through the wire insulation".



The professional probes have a clip that supports the wire and a needle that penetrates the insulation.

If you could make yourself one of these it might help.

Then probe every signal that the ECU uses to verify "OK to start" and do not make any assumptions.
The #1 cause of failed electrical troubleshooting is making incorrect assumptions because you dont have the tools to verify.
That and - Write shit down :-)

Thank you for the advice, im running out of time so im starting to move on to other things i can build and work on in the time being. Im going to hook the multimeter up to the starter and see what thats doing, and if it doesnt uncover anything i might start going through things systematically like you advised. But i might save it for a subaru specialist that could probably troubleshoot it faster.

[Gords_zenith]

Originally Posted by im_topher

Checked that, its all good, i did a once over on every fuse in the car, they are all good.

Did you see he other posts I posted in this thread? I looked at my battery connector and there a fusible link for the alternator 140A. That could be part of the problem too.

[im_topher]

Originally Posted by Gords_zenith

Did you see he other posts I posted in this thread? I looked at my battery connector and there a fusible link for the alternator 140A. That could be part of the problem too.

Ill check this out.

On a related note, we started filming the rebuild of the car, theres yet another attempt to start up in the beginning of this video.

[ame="https://www.youtube.com/watch?v=JAfzPHA_QcY"]BRZ Resurrection Part 1 - YouTube[/ame]

If anyone is still interested in learning how i get this thing to start, ill be posting more videos here in my build thread and ill be continuously testing more things when i have spare time.

[im_topher]

Hey all, car still hasnt started, to be fair i havent worked on getting it to start much in recent weeks. I was inside the car yesterday and the computer(stereo?) gave me the blank stare it always does, and i wanted to bring that up and ask, will the computer being dead stop the car from starting? Heres a picture.


is program loading really necessary?

[RIP.S2000]

Originally Posted by im_topher

Hey all, car still hasnt started, to be fair i havent worked on getting it to start much in recent weeks. I was inside the car yesterday and the computer(stereo?) gave me the blank stare it always does, and i wanted to bring that up and ask, will the computer being dead stop the car from starting? Heres a picture.


is program loading really necessary?

Not that I know of. From what I understand, the SD is only for the navigation and head unit. And each SD is unique to the car. I'm 90% sure it has nothing to do with the actual vehicle itself. Good luck with this project man. I'd like to see this thing started.

Sent from my SAMSUNG-SM-N910A using Tapatalk

[im_topher]

Originally Posted by RIP.S2000

Not that I know of. From what I understand, the SD is only for the navigation and head unit. And each SD is unique to the car. I'm 90% sure it has nothing to do with the actual vehicle itself. Good luck with this project man. I'd like to see this thing started.

Sent from my SAMSUNG-SM-N910A using Tapatalk

thank you, i think its going to the dealership tomorrow so hopefully next week ill have a video of it firing up. Still alot of work to be done but its finally looking like a car and thats got me pretty stoked.

[im_topher]

ok guys, i took it to the dealership heres what ive learned.
they cannot get ANY communication to the ECU, even if they power it up externally, its not talking to the OBD2 port. They said its something in that engine bay fuse box that is messed up, they wanted to order a new one for $1500 and install it, ticket price well over 4K to do that. So i have the car back at my house, and im working on that box. They said there is a computer in there, ive looked everywhere, i see no computer chips or anything.

I do have something a little strange ( or at least to me ) it looks like all the main wires running into the box are carrying 12v, shouldnt there be a ground wire coming in somewhere? Or do fuse boxes not need ground?

Also does anyone know about the immobilizer on this car and what it does? Does it stop communication to the ECU?

[Ashikabi]

Can the obd port be bad? I had mine not connect for flashing unless I pull the plug toward the steering wheel

[im_topher]

Originally Posted by Ashikabi

Can the obd port be bad? I had mine not connect for flashing unless I pull the plug toward the steering wheel

the port is working, i can scan for codes and it scans and says "cannot contact the ECM/PCM"

Or maybe "cannot connect to ECM/PCM"

something along those lines, so its working. Oh also i can hit the reset button and hear it dong things with the car. So its working.

I just filmed this video of me tearing into the wiring, i swear im not doing this to pimp my youtube channel, but if anyone is wondering where exactly i am with this and has any ideas please check out the last 5 mins of this video, maybe youll see me doing something wrong that could fix it.

[ame="https://www.youtube.com/watch?v=KqFnEBNM00Q"]BRZ Resurrection Pt 13 - Diagnosing A Lack Of Vroom - YouTube[/ame]

[stugray]

At work we would start with a "fish-bone failure analysis".

It pretty much defines the problem "car wont start" (the head of the fish) and then tries to identify all the things that could lead to the car not starting.
One example: ECU not booting - becomes one of the "bones" on the fish

Then for each and every "bone" defined, you write down the knowns, unknowns, and assumptions (things you assume to be true, but havent verified).

Then you begin working on each and every bone one at a time.
As you do this, you will rule out particular failure modes, or add new ones.

Then it wouldnt hurt if you can make simple instructions to test each and every "assumption". Perform the test yourself on your car then have someone with a working car perform the same test.
Record the results carefully.

Problems like this can seem hopeless if you dont have a plan of attack and take LOTS of notes.
I would become very familiar with the wiring diagrams as well.

[im_topher]

Originally Posted by stugray

At work we would start with a "fish-bone failure analysis".

It pretty much defines the problem "car wont start" (the head of the fish) and then tries to identify all the things that could lead to the car not starting.
One example: ECU not booting - becomes one of the "bones" on the fish

Then for each and every "bone" defined, you write down the knowns, unknowns, and assumptions (things you assume to be true, but havent verified).

Then you begin working on each and every bone one at a time.
As you do this, you will rule out particular failure modes, or add new ones.

Then it wouldnt hurt if you can make simple instructions to test each and every "assumption". Perform the test yourself on your car then have someone with a working car perform the same test.
Record the results carefully.

Problems like this can seem hopeless if you dont have a plan of attack and take LOTS of notes.
I would become very familiar with the wiring diagrams as well.

thats one issue im having, the wiring diagrams look like a different language to me, i under stand some basic things but im not getting the whole picture most of the time. For instance im trying to find how the ECU gets to ground, and im getting stumped.. Im not done trying, but its taking a while.

[im_topher]

alot of people online have been posting about different computers disabling the engine because the car noticed it was in a wreck, is this something i need to be worried about?

I keep running through the wiring harness looking for faults, but after a while im feeling like its not the cause, i have no logical reason to think that other than i cant find any damage and everything looks stock.

Any way to tell if an ECU is fried?

[im_topher]

Hey all, i know alot of people have tuned out of this thread but i have one more question.
Heres where im at, i did a visual inspection on the fuse box, tested every fuse, tested every relay. Got under the dash and pulled out the ECM and visually inspected it, tested wires going to that, tested all grounds. Everything looks good. I ordered a new fuse box and all the wiring that goes with it, and ill be replacing that next week.

Someone on my page recently posted that there is a "little computer chip" inside or near the fuse box. That may be damaged on my car. I havent seen anything like that, im pretty sure there isnt one in my fuse box.
I heard rumors of a computer chip similar from the dealership when i took it in. But never found it.

Does anyone know anything about this mysterious chip and where it might be? Or was supposed to be but possibly got blown off my car during the accident? I have another BRZ now i can go look at for reference.

Also i have the wiring diagram but i havent found anything about a chip on there yet.

Whats this chip and whys it being a pain in my ****!?