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N62 Z3 Part 7: More Wiring & First INPA hook-up

At this point I was pretty focused on the test start - although I did get a little sidetracked when I discovered that auxiliary fusebox I bought fit in a slot in the Z3 DME box perfectly, so I decided to go ahead and redo the fuse setup to simplify things a bit

Looks so nice!

This is what the fusebox wiring harness looked like. The red (constant power) line was not tape wrapped yet because I ended up being trimming it to be shorter but wanted to wait until it was in place to do so

Next time I worked on the car I went ahead and got everything in place... I wanted to make some sort of tangible progress and communicating with the N62 DME via the Z3 OBD2 port would be my first step before attempting a test start. I can't attempt a test start quite yet as I am waiting on some electrical pins in order to finish the starter wiring

Below shows the positive cable which supplies the distribution block with power - the very bottom left is the main power cable which feeds directly to the battery. This ultimately supplies the PWM fan, fusebox and IVM with constant power

Some terminals had to be left without harnesses for now, as I wait for my depinning tool to arrive. They do have terminals on them though. This way, I can plug them into their respective spots in the meantime as pictured below

This was how everything looked before the DME was plugged in

And then... with the DME plugged in

I also installed the engine wiring harness as there are a few lines that run in the engine harness between DME and IVM. The IVM has the green terminals

And then a test on INPA...

Success! Not a huge deal all things considered, you can communicate to a DME with very few things working - but now I am ready to reinstall the engine and prepare for a test start once the last electrical pins get here so I can finish the starter wiring. The starter wiring in particular is rather interesting, as it had to be diverted to run into the IVM. So I am hoping that works, but that is certainly a big question mark for now

Before finishing up for the night I did go ahead and tidy things up a little bit, including trimming the cover for the distribution block (which was not fully clipped in in the picture)

I also ran the electronic pedal wires, first I had to tape them all up neatly

This is where they go into the firewall - used an existing grommet off another parts car and drilled a hole in the middle

And the other side... still deciding the final routing, but they are color coded on both sides to make things easier to match up. I will mock these up into a pedal temporarily for testing purposes

Then I removed the exhaust to install the last plug on the engine wiring harness, for the starter. It's a little hard to see, but I also installed the large power supply cable at this point - the one with the heat shield and blue ziptie. I also installed the small signal line

With the heat shield back on

And in it's home, behind the header

Then I tidied up some of the plugs I confirmed were for the automatic transmission and rear O2's. I think rear O2's are still enabled in my tune so I may need to figure something out for that but for now they are not in the way

Then I reinstalled the engine

And knowing that the wiring stuff didn't start a fire last time, I went ahead and plugged in the engine harness on the engine

My very temporary setup for the grounds

And just some INPA screens... looking good so far, as far as I can tell. Won't reveal much until an attempted first start though. And won't attempt a first start until I verify the wiring again...

I am about to attempt a first start but went ahead and wired the pedal in for now... in it's (obviously) temporary position

And threw the gauge cluster in...

Confirmed the pedal was working as well

Okay... up next is to check my wiring again... I will double check the wiring diagrams and then double check that my wiring is all correct. Hopefully there are no surprises and I can go for a first start attempt soon!



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