Help with Idle up Wiring into the Ma70 to Jza70

[92TealSupra]

To start Ia m wiring a 1jz-gte out of a jza70 into my '91 Supra.



Alright! Well There is no real way for me to understand this and how it works.
At the alternator there is a Round plug that goes into it, no problem. There is also a wire that is thick with the rubber protection that goes on to it.

Now what I don't understand is the two larger black wires that were CUT from my harness. When i use a DVOM it is telling me that they connector to the other thick wire that goes to the alternator.

Here is a pick, as you can see the Newer taped looking wire is what I can't figure out, it was cut. I added that on there so it would connect to something.

The round one I know, and the one with the gray rubberized one I know where those go, I can't figure out the other one, it was CUT* when I got this harness.

This is what I have on the car, the C1 plug, the Round alternator plug and the huge wire that goes on the alternator from the 7M.

If there is someoen that can walk me through this process that would be great!!!

 

[2JZ_MA70]

If it is B+ wire it most likely goes to the starter... Its been a while since I have seen stock 7M body harness... Mine is 1/2 gone... =)

If it is black wires they most likely go to the starter. I guess its short because it was cut and spliced.... there is similar gauge wires that go to the battery positive... but they are white. Hope that helps.

 

[92TealSupra]

If it is B+ wire it most likely goes to the starter... Its been a while since I have seen stock 7M body harness... Mine is 1/2 gone... =)

If it is black wires they most likely go to the starter. I guess its short because it was cut and spliced.... there is similar gauge wires that go to the battery positive... but they are white. Hope that helps.

I am unsure, because I have the starter hanress so it can't be that! hope someoen chimes in with a 1jz!

 

[JonnyRedline]

Here is a pick, as you can see the Newer taped looking wire is what I can't figure out, it was cut. I added that on there so it would connect to something.

That wire used to connect to the 7m alternator power. You can use a butt connector to connect a new power wire from your jz alternator to those 2 smaller power wires. Thats it for your charging power wires. You will also need to connect the 3 wires from the round plug in the alternator on the jz and connect them to the corresponding wires in the engine bay, it will already be a plug that went to your 7m alternator, very easy. There should be TWO more big power wires, one for the fuse box, and one that goes to the starter.

 

[92TealSupra]

That wire used to connect to the 7m alternator power. You can use a butt connector to connect a new power wire from your jz alternator to those 2 smaller power wires. Thats it for your charging power wires. You will also need to connect the 3 wires from the round plug in the alternator on the jz and connect them to the corresponding wires in the engine bay, it will already be a plug that went to your 7m alternator, very easy. There should be TWO more big power wires, one for the fuse box, and one that goes to the starter.

Yeah I got the round plugs and the c1 plug figured out thank god now.

The thing is I don't think the starter wires go to the alternator or near that location. It looks like the two black wires go to the 7M alternator wire or ( primary ) Wire; Because when I DVOM it the lead that goes to the alternator goes to the two black wires! So I am thinking the two black wires are suppose to go to the alternator primary from the engine bay harness I have pictured next to the C1 plug.

:!Remember!: The starter has it's own harness and I was able to crank over the starter with the harness hooked up to anything but 1 wire.

The starter is a ground, a power wire which goes to the battery, and a single Black/Blue wire which lets current flow when you turn the key

I am just wondering why the two black wires were cut and what it looks like when they're not. I have to extended these wires like 3 feet or so to meet up with the 7M primary for the alternator? Doesn't make sense!!


Hope someone chimes in.

 

[2JZ_MA70]

Oh that first pic is off the 1JZ harness... LOL.. take a pic of the entire alternator harness... I think those wires will attach to your 7M alternator wires.

 

[92TealSupra]

Oh that first pic is off the 1JZ harness... LOL.. take a pic of the entire alternator harness... I think those wires will attach to your 7M alternator wires.

Well the 7m alternator round plug has 3 wires, I have already wired thsoe up.

The main thing now is the two wires that were cut would have had to go to the body harness even on a jza70, and there on the totally opposite side of the motor bay, The two wires that are together I have as ONE as you can see. It's the Fate looking one of the three I took a pic of.

what I don't understand is how they go all the way to the fuse box location, to the 7m alternator area, unless the jza70 engine bay harness has a plug somewhere else.

 

[JonnyRedline]

Well the 7m alternator round plug has 3 wires, I have already wired thsoe up.

The main thing now is the two wires that were cut would have had to go to the body harness even on a jza70, and there on the totally opposite side of the motor bay, The two wires that are together I have as ONE as you can see. It's the Fate looking one of the three I took a pic of.

what I don't understand is how they go all the way to the fuse box location, to the 7m alternator area, unless the jza70 engine bay harness has a plug somewhere else.

those two black cut wires that go into the harness area under the fuse box, go directly to the alternator power wire from the jz engine. those wires used to go to the 7m alternator. just use a butt connector that you can get from sears hardware, it will have 2 set screws and it will be a brass looking tube, it comes with a big piece of heat shrink. use that to connect your new power wire from the jz alt to those two wires.

 

[JonnyRedline]

Yeah I got the round plugs and the c1 plug figured out thank god now.

The thing is I don't think the starter wires go to the alternator or near that location. It looks like the two black wires go to the 7M alternator wire or ( primary ) Wire; Because when I DVOM it the lead that goes to the alternator goes to the two black wires! So I am thinking the two black wires are suppose to go to the alternator primary from the engine bay harness I have pictured next to the C1 plug.

:!Remember!: The starter has it's own harness and I was able to crank over the starter with the harness hooked up to anything but 1 wire.

The starter is a ground, a power wire which goes to the battery, and a single Black/Blue wire which lets current flow when you turn the key

I am just wondering why the two black wires were cut and what it looks like when they're not. I have to extended these wires like 3 feet or so to meet up with the 7M primary for the alternator? Doesn't make sense!!


Hope someone chimes in.

you just answered your own question.

 

[2JZ_MA70]

those two black cut wires that go into the harness area under the fuse box, go directly to the alternator power wire from the jz engine. those wires used to go to the 7m alternator. just use a butt connector that you can get from sears hardware, it will have 2 set screws and it will be a brass looking tube, it comes with a big piece of heat shrink. use that to connect your new power wire from the jz alt to those two wires.

second that....

 

[92TealSupra]

Ahh! I don't know what to think, and I will not guess! With anyone's luck I will be powering a ground lol.

 

[2JZ_MA70]

The wires are the charging circuit of the alternator. Just crimp (dont soder heavy wires like that) to the Original 7M alternator charging wire.

Just Like JonnyRedLine was saying....

 

[92TealSupra]

Yup I thought I was on track with everything, thank god I was. That is what I am goign to do. I was looking for pictures of a wire going from the alternator to the wire, and I never saw it, i found out it is hidden under the radiator support.

 

[92TealSupra]

So I have another Q!

on the M1 Plug there si a purple wire, I guess this is its function

From defogger relay Signal is switched to mass when defogger engaged. Signal is +12v when not. Used for idle up. PURPLE

I am not sure what that is, but I took the DVOM and found out one of those wires goes to the brake.

I wired it to the

Green/white on the jza70 which is this

TO ECU STOP signal, I am not sure what the stop signal nor this purple wire are anyone?


I am sure someone can go under the dash and see what wire goes to the purple on the M1 plug from their JZA70 harness please help me out here!

 

[2JZ_MA70]

The IDL-UP on the JZA70 is "ELS" terminal and is coming from the "TAIL" fuse and it should be 12V=on 0v=off. On the MA70 terminal "LP" it is the opposite and it is coming from the healight relay coil ground circuit. 0v=on 12v=off.

The "STP" terminal is optional the car will be fine without it. I dont know the exact function.

On the MA70 the "DFG" is the (defoger relay Idle up) that is not used on the JZA70. But could be integrated with the method below.

You can have multiple inputs to the ELS terminal in the JZA70 and that is how you can get this to work really nice. You would need few diodes. Then run wires from the components that you wish to trigger the ELS to the diodes. Make sure you have 12v on the wire when the component is on. I did this on Soarer 1JZ swap. Toyota calls it IdleUp Diode. They probably used it in more than one car and ou might be able to purchase it directly.

This is based on the Wiring diagrams that I have seen. If anyone has anything different please share.

 

[92TealSupra]

The IDL-UP on the JZA70 is "ELS" terminal and is coming from the "TAIL" fuse and it should be 12V=on 0v=off. On the MA70 it is the opposite and it is coming from the healight relay coil ground circuit. 0v=on 12v=off. Don't use the purple wire.

So delete the Purple wire? Doesn't it get used for defogger.. Also from other things it seems important to use!

so bascially what do i do with the purple wire here! I have it wired into the stop signal on the ecu, may be a bad choice. I am onyly having issues with what I have posted here.

And what does Idle up exactly mean, is that for the engine?

Also one more quick Q on the B2 Plug which is white, the Red/yellow is for Headlight relay used fro idle up. Signal is switched to mass when lgihts are on, does these correspond?

Last Q, the Green/White wire coming from the JZA70 hanress is used for ECU Stop Signal? What do I wire that to on the Ma70

Thanks! This is making my job easier!

 

[92TealSupra]

So what is "ELS" in reality? Do I need it? What is its main function. I have to find out what to do with the purple wire on ( M1 ) and the Red/Yellow Wire on the (b2), and the Green/White On the jza70 hanress which is ECU stop signal, I need to figure where to wire these in.

 

[2JZ_MA70]

Ok The IDLE UP function is to prevent the engine from bogging down when heavy electrical loads are on. It signals the ECU to increase the IDLE speed. It is not critical for engine operation but it is nice to have.

To make it work correctly you need to use 12v=on signals run them through a one way diode and hook it to the ELS terminal on the ECU. The diodes will prevent voltage backfeeding on circuits that are off.

If you only use one signal (when lights are on for example.) you dont need the diodes but you have to tap into a wire that is between the switch and the consumer.

I ran mine without the STP ( brake lights ) terminal


ELS = LP + DFG

 

[2JZ_MA70]

you have more than enough info to get this done. let me know if you need anything else. got to go to bed now... =)

 

[92TealSupra]

Ok The IDLE UP function is to prevent the engine from bogging down when heavy electrical loads are on. It signals the ECU to increase the IDLE speed. It is not critical for engine operation but it is nice to have.

To make it work correctly you need to use 12v=on signals run them through a one way diode and hook it to the ELS terminal on the ECU. The diodes will prevent voltage backfeeding on circuits that are off.

If you only use one signal (when lights are on for example.) you dont need the diodes but you have to tap into a wire that is between the switch and the consumer.

I ran mine without the STP ( brake lights ) terminal

So for example the red/yellow which is headlight relay used for idle up, and the purple which is idle up for defogger. What wires off the jza70 hanress should hook up to those two wires?

Also the STP signal is not used I guess, or not really important on our cars?