Wiring for a race car

MDCmotorsports

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This is going to be a work in motion: How to gun the ma70 chassis of its bull shit wiring that a race car does not need. For instance power steering ecu/relay, heater and ac relay etc.

To begin, Im working in the black hole they call the passenger side fuse/relay block. I believe the manual calls it #4.

1.) What does the circuit opening relay do. I traced it back to the fuel pump relay. A relay on top of a relay? Please explain.

2.) Can some one show me a picture of all the hvac connections (plugs) found on the passenger side of the car.

3.) The ecu has two plugs that come from the wiring harness. Where does #3 come from? I can not find it. I have yet to start snipping and cutting wires so i know its not on the shop floor.

Thanks in advance, more progress to come.
 

Racer48

the man on dirt
i am actually in the process of building a road corse car at the moment. To simplify the wiring i riped every wire and fuze block out of the car, and im going to put a painless either 12 or 18 circuit universal harness. Then for the wiring under the hood since im going to be running a 1uz with a mega squirt im going to build a harness with just the basic necessitys.
 

Flateric

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I would love to help you out with those plugs man and it is possible I would remember where they go and such if you post some pics of em. Unfortunately the wiring in my car nowadays is far from stock after my swap.

But the circuit opening relay is for the power door locks is it not? Fairly certain about that one.
 

MDCmotorsports

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Flateric;1776664 said:
I would love to help you out with those plugs man and it is possible I would remember where they go and such if you post some pics of em. Unfortunately the wiring in my car nowadays is far from stock after my swap.

But the circuit opening relay is for the power door locks is it not? Fairly certain about that one.

Im out of a cpu right now. If you give me an email, ill shoot you pictures and then maybe you can post them. The circuit opening relay is for the fuel pump system as i found out.
 

MDCmotorsports

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Ok Ive got some help so far. Leta continue to dig here...
Junction block #1 (drivers kick panel)
-Need to know what plug numbers 1B, 1C, 1A, F, G, D, M, L, N, K, AND 1J go to.
-What does the intergration relay do on the back side of Junction block 1
 
Dude, you know the TEWD has diagrams of every plug, what connects to what junction block, the functions of each relay, wiring harness routing, etc, etc all in it right?

Like this: http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=23

And this: http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=51

And this: http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=52

And if you have another year of vehicle that might have different colors (they're mostly the same) there are pre-89 and other TEWDs floating around on the internet for free too. Or just buy the one for your car.
 

MDCmotorsports

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rtrdpenguin;1776982 said:
Dude, you know the TEWD has diagrams of every plug, what connects to what junction block, the functions of each relay, wiring harness routing, etc, etc all in it right?

Like this: http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=23

And this: http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=51

And this: http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=52

And if you have another year of vehicle that might have different colors (they're mostly the same) there are pre-89 and other TEWDs floating around on the internet for free too. Or just buy the one for your car.

Well holy shit. All these years and i had no clue. Shows ya you CAN teach an old dog new tricks.
 

IJ.

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rtrdpenguin;1776982 said:
Dude, you know the TEWD has diagrams of every plug, what connects to what junction block, the functions of each relay, wiring harness routing, etc, etc all in it right?

Like this: http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=23

And this: http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=51

And this: http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=52

And if you have another year of vehicle that might have different colors (they're mostly the same) there are pre-89 and other TEWDs floating around on the internet for free too. Or just buy the one for your car.

Toyota have use much the same colour combinations for ALL their cars :)

Eventually you get to the point that you recognise them in a bundle and know where they're going.
 

MDCmotorsports

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Well after getting a wiring diagram in my hands, I have found that toyota integrated too many essential circuits to keep the car running with non essential wiring.
Because of this, Ive ripped the entire wiring harness from the car, under the hood and in the cab.
It has been decided to build/use a 12 circuit wiring harness.
Im going megasquirt ecu and building a harness for under the hood.