Need help with running power wires in engine bay

[MarkIII4Me]

So I tested all of my grounds and they are good, but I still can't get any power to the ECU. I am not using the original power wire coming off of the battery. So I don't know if I'm missing something. I have a power line running to the starter, running to the alternator, and have the wires coming out of the fuse box going to the positive on the battery. What am I missing?


Apparently this group of wires runs power to the fuse box:

When that is connected. This power wire also coming from the fuse box is live (appears blue on top, but white on the bottom:

But what does it go to?

Strange thing is that there is a ground wire coming from the passenger side fender. It appears to be grounded when not even bolted down to anything? What does that mean?


This is really driving me crazy. I turn the key and all that comes on are my guages, radio, lights and climate control. Nothing spliced into my ECU power is coming on. No WB, no EVC, VPC, TEMS controller nothing. When I tested the power going to the fuses in the engine bay, half of them don't have any juice going through. I figure I must be shorting out someone. I used to think this was due to not having most of my grounds connected. But now they all are.

Ideas?

 

[mk3-4-me]

i believe that blue/white wire attaches to the pos battery terminal. Im pretty sure thats the power to the fuse box/everything. Thats what was keeping my car from getting power, bad connection.

 

[Nick M]

Get the Toyota Electrical Wiring Diagram for your year.

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=36

 

[MarkIII4Me]

Nick, I already have the wiring diagram. I did just realize something and now I feel stupid. I had the EFI fuse pulled for safety (no oil in crankcase). So that would explain why everything spliced into the ECU isn't powering on. However, I don't see how this would affect the TEMS controller. I have a 90T so the unit should pull the power from the cabin harness. I shouldn't need to run power to it off of the old TEMS switch plug.

 

[MarkIII4Me]

Yep. I'm a dumbass. Plugged in the EFI fuse and it was christmas.

Everything juiced-up except the HKS TEMS Controller. I'll have to run that power wire to it I guess.

 

[IJ.]

Damn electricity just won't jump that last 5mm gap
(lost count how many times I've spent hours trouble shooting to find it's a dumbass related cause of my own making)

 

[MarkIII4Me]

Tell me about it IJ. It's one of the main reasons I quite drinkin and tinkering

I didn't even bother hooking that blue/white wire back into the battery. Do I even need to? I mean, it gets power off of the wire that I have connected to the alternator. What would be the point of plugging a live wire into the battery? All I can figure is it use to connect to the power line running to the starter. What else could it be?

 

[Nick M]

If you have the EWD, why don't you check it? It tells you what that line is for. Don't sweat a small mistake. Every body does it. Many here won't admit they were wrong when posting. That says you have some character.

My 91 says the blue wire with the white tracer (L-W) is from the 30 amp cb in left kick panel and is used for door locks, power windows, power seat, sun roof, etc.