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Discussion Starter · #222 · (Edited)
Good luck getting that first spin - i've spent hours going over mine getting nothing - I may have a dead inverter but I can't figure it out - ready to just quit o_O
Brother nooooo! take a step back, and if you built your own harness, no disrespect but please go out and buy the transmission one at least, I've talked to another guy on this forum who said he had a tough time at first with the one he built from scratch. You need the factory resolvers to inverter twisted shielded pair cables to be perfect. I wish you were local.
 

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Brother nooooo! take a step back, and if you built your own harness, no disrespect but please go out and buy the transmission one at least, I've talked to another guy on this forum who said he had a tough time at first with the one he built from scratch. You need the factory resolvers to inverter twisted shield pair cables to be perfect. I wish you were local.
maybe i'll keep my eye out- thought I just saw a link for one but now I can't find it
 

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Discussion Starter · #227 · (Edited)
alright, enuff word's time for Phase I - aka Operation: "Spin You S.O.B." [wait is this a family friendly forum?]

Automotive tire Motor vehicle Tread Electrical wiring Gas


and here are our Take Aways from that first attempt:

1. the VCU does not come Pre Programmed !
2. the Safety Neutral Switch pinout I found is dead wrong!
 

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Discussion Starter · #228 · (Edited)
We need to program two things in the VCU (Vehicle Control Unit) ie that Open Source circus board

1. Maximum torque values for both Drive and Reverse, the VCU comes with both of those values set to 0, so you will be pressing the throttle till the cows come home and no cows will ever arrive.

2. We need to calibrate the throttle, more specifically zero throttle and maximum throttle values


Rectangle Font Screenshot Number Software


Rectangle Font Screenshot Parallel Number
 

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Discussion Starter · #229 ·
I took on the transmission Neutral Safety Switch pinout next [there's four hours of my life I will never get back, makes Common Core Math look intuitive]

Wood Automotive tire Rectangle Material property Flooring


Light Motor vehicle Automotive fuel system Gas Automotive exterior
 

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Discussion Starter · #230 · (Edited)
I always get so confused trying to shift automagical gear boxes without the floor shifter, I have to take a moment and convince my small brain, it is all opposite

so since you push the floor shifter forward to put the thing in Park, that moves the actual lever on the side of the transmission back, putting it in what I would call the 10 am position

Reverse being straight up, so 12:00 o'clcok

Neutral at 1:00 o'clock

and Driver at 2:00 o'clock

Millennials: the circle with numbers below is called an analog clock, they used to hang on the walls in our classrooms (from after WWWII until WWW ha ha) tongue and cheek people, tongue and cheek

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Discussion Starter · #234 ·
I bet that felt great! - I'm redoing my harness now and just doing one side to try and get this thing to spin - or at the least verify I have a bad inverter
It sure did and I would be lying to you if I said I got it right on the first try, there are just too many pieces to the puzzle [I'm looking at you Safety Neutral Switch!], but having both the stock OEM "Inverter" harness as well as the "Transmission" harness took care of 87% of the wiring. I know you catch my drift.
 

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Discussion Starter · #235 · (Edited)
so on to Phase II (Operation Tumbleweed)

  • in this phase we are going to complete building the controller (VCU) by soldering on the other 20 pin connector header as well as the tiny header for the tiny red WiFi card
Passive circuit component Circuit component Hardware programmer Computer data storage Font


  • we will make some sort of a mechanical bracket to lock the input shaft, because preventing it from spinning will force Motor Generator 1 (MG1) to help MG2 spin the output shaft

  • and we will build / connect the rest of the wiring harness (hewk we may even loom it, professional like and such!)

  • I don't think we will wire up the external electrical transmission fluid aka oil pump yet


Rectangle Computer data storage Wood Font Flash memory
 

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You're doing yeoman's work showing the steps you're taking to get this all spinning. Really appreciate it! I'm considering swapping an 87 Dodge pickup, so this is extremely helpful in the figuring process. Keep it up!
 

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OK, now we get to the Meat and Potatoes of the entire operation, the Four Most Important Cables, aka the Synchronous Serial Communication !

Yes I said cables instead of wires, just trying to get my terminology right, a wire is just one conductor, a cable has many wires inside it, as do these. Each one of these special cables has two wires inside it, a white one and a black one, they are twisted together, and shielded, giving us what is commonly referred to as a twisted shielded pair.

So think of these wires as an 8 lane Super Highway that runs between the Inverter and the Controller (aka VCU Vehicle Control Unit) think Autobahn

Don't worry about the pins that have the brown wires connect to them, they loop back on to themselves.

X I believe we cut the wire on this pin and don't use it I am not sure what it's for

View attachment 124700

MTH - (white wire)goes to VCU B Connector Pin 7
MTH + (black wire)goes to VCU B Connector Pin 8
HTM - (white wire)goes to VCU B Connector Pin 9
HTM + (black wire)goes to VCU B Connector Pin 10
REQ - (white wire)goes to VCU B Connector Pin 11
REQ + (black wire)goes to VCU B Connector Pin 12
CLK - (white wire)goes to VCU B Connector Pin 13
CLK + (black wire)goes to VCU B Connector Pin 14
GI is the engine RPM signal from the engine ECU, not needed, cut short, fold back and heat shrink over the fold (adhesive lined), don't remove the pin. To preserve IP rating.
 

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then on to the front side, here you twist, pry, cuss, repeat...

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in case you want to pick one up of these CRAFTSMAN 3/32" tiny screw drivers Part Number: 41640 (my stock portfolio thanks you)

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Have a read of the application specification for these connectors.


The white TPA piece should not be fully removed!
 

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Excellent question, no they are a strange design and I don't fully get it, but they come from the Inverter plug and do a U turn back to the Inverter, so they do not go to the VCU, I included some pics of one of them close up. Here is a wiring diagram found on the Open Inverter Wiki, I labeled what's what on it, the attached one, you may be able to enlarge easier.

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The DRN pins on the inverter provide clean grounds for the drain wires inside the twisted pair, and resolver cable (along with GI). They loop back partway and connect to the drain wire inside the cable assembly. They are important to prevent EMI to signals within these cables. They are all brown. Leave them be!
 
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