Wiring guide for AIT and MAP sensor?(AEM)

[MRSUPRA]

Does anyone have any information on how to wire up the AEM 3.5 map sensor and the AIT sensor. I did some searching and couldn't find anything about which wire goes where. The AIT sensor has 2 black wires and the Map sensor has a red, green and black wire. Any info is appreciated. I'm trying to get the AEM tuned by next week. Thanks.

Matt

 

[drbowser3]

I don't remeber which wire is which on the MAP sensor, AIT has no polarity, as far as which wires in the harness, the AEM comes with a pin-out, I used to know the color and pin numbers, but it has been 1+ years since I installed an AEM. The AEM forum or even the tech section here should help, just do a quick search.

 

[turbogate]

Taken from the AEM forums in our section (quotes). I used the same info on my car, and it worked perfectly. Mine is a 89+ so I had to double check on the pin/wire location/color etc Hope that helps

IAT:
2 black wires


MAP:
1 black
1 red
1 green

Trev here are some additional info
(wiring for the 1987, 88 Supras)...
***MAP***
Red Wire = The MAP is a 5V reference
You can splice into the stock MAF wire (Blue W/Red stripe) going to AEM 10C or use the spare connector plug Pin 2-1 and run a new wire.
Black Wire = The ground must be sensor/analog ground
now this ones tricky as you will see there are two brown wires in the MAF labeled E1,E2 (EMS 9A,13C) and the stock MAF uses E1 for the Karmen air flow and E2 for the AIT. E1 = Computer Ground, E2 = Sensor Ground. You can either splice E2 and feed them to the AIT and the MAP or run a new wire to the optional connector plug Pin 2-2. Note: E2 goes to the throttle sensor and many other coolant sensors while E1 goes direct to the ECU & ground. I used E1 for my Map the first time around and am getting allot of noise from the MAP sensor so I will be changing mine to Pin 2-2.
Green Wire = MAF signal you can either use the light green W/Red stripe from the MAF and cut the 22c wire on the ECU side and move it to the optional connector 2-5 or run a new wire to it.
***AIT***
Two Black Wires and since it a resistor, it does not matter which one you use. One goes to the brown wire (E2-AEM 13C) on the MAF and the other goes to the light green (No stripe) wire going back to 8C on the AEM.

 

[MRSUPRA]

Thanks guys. Keep is coming.

 

[MRSUPRA]

Ok I think I got most figured out except the green signal wire.

Map sensor: Red-1B
Black-9B or 4C
Greed- 17A (dedicated). The problem is that there is no wire going into the connector at this location. How did you guys wire it up with no wire comming out of the connector?

 

[drbowser3]

Ok I think I got most figured out except the green signal wire.

Map sensor: Red-1B
Black-9B or 4C
Greed- 17A (dedicated). The problem is that there is no wire going into the connector at this location. How did you guys wire it up with no wire comming out of the connector?

Make sure you are looking at it right, if you have the diagram from AEM, it shows the ECU side, act as though you are pluging the harness into the paper, easiest way to prevent yourself from cutting the wrong wires.

 

[MRSUPRA]

/\ Got that covered.

But there is still no wire for 17A. And according to the chart, there is not supposed to be one. Just wondering how you are supposed to connect the green signal wire to 17A without anything to connect it to?

 

[drbowser3]

/\ Got that covered.

But there is still no wire for 17A. And according to the chart, there is not supposed to be one. Just wondering how you are supposed to connect the green signal wire to 17A without anything to connect it to?

Good call, I forgot about that. What I think I did on mine, like I said it has been 1+ years since I wired it, but 16A is an available switched ground, I didn't use it. I de-pinned that wire(16A) and moved it to slot 17A. I then spliced into the wires on the firewall around the valve covers. It was easier than splicing in at the ECU and running new wires.

Hope this helps.
Denny

 

[MRSUPRA]

Damn, I was afraid you were going to give me an answer like that.
Thanks for the help Denny.

 

[drbowser3]

Damn, I was afraid you were going to give me an answer like that.
Thanks for the help Denny.

Its no too bad to do. Just get a long skinny pick and go for it. Be careful ot to damage the plug, it helps if you have old harnesses around to practice on. The stock ECU plugs aren't too bad to de-pin. They are not as brittle as the engine bay plugs.

 

[MRSUPRA]

I just looked on the chart.
16A-1989-1992 MK111 AEM Name I/O Availability
EGR temp LS#2 Output Avail, switched ground, 1.5A max

Does that sound familiar?

 

[turbogate]

In my post above, look the green wire description toward the bottom of the quote. That's what I did (it's been a while, so I don't remember the details) Basically you can use one of the maf wire that's no longer used from the original air flow meter harness. It says to look for the green with red stripe wire, but I would double check. Then you would just move that pin from it's location to that 17c location that the AEM manual says or whichever is the one for your year aem box.

The only extra wire I had to add on the AEM is my wideband signal wire. Like drbowser3 said, make sure you are using the right pin location. That's how people misplace pins, and mess up their box and give the AEM a bad rap :icon_bigg It almost happened to me, I could'nt figure out why I was getting max engine load until I realize I have the green wire in the wrong pin.

 

[MRSUPRA]

OK, I see. Your saying remove the air flow meter wire from its connector location(2B) and relocate it to 17a so it will plug into the AEM at that point. Then hook the MAP signal wire from the map sensor to that same wire where it plugs into the airflow meter.

 

[turbogate]

OK, I see. Your saying remove the air flow meter wire from its connector location(2B) and relocate it to 17a so it will plug into the AEM at that point. Then hook the MAP signal wire from the map sensor to that same wire where it plugs into the airflow meter.

You got it. The only reason you would want to run fresh wires from the sensors into the cabin, would be if you feel your harness is in really bad shape, or you want to keep these connectors in case you want to reverse everything (if selling car etc). If you do end-up wanting to put the stock ecu back one day, you can still redo the AFM wire anyways.

The same goes for the AIT by the way. You can use existing AFM wires and if I remember correctly, no pin relocation is necessary for the AIT, and all the wires you need are also on that AFM harness (almost 100% positive.)

Since I'm running an FFIM, I seperated the AFM wires from the section that includes all the temp/oil sensors etc and brought those wires to the driver side of the engine. My AIT is under the driver side headlight, and my MAP sensor is "freely laying" somewhere close to my igniter using the nipple adapter for the vacuum signal instead of hard mounting it. That's why I brought those wires to that side. Hope that helps.

 

[MRSUPRA]

Yeah I just about have everything all wired up exept the Map signal wire and the wideband output.
Which brings me to this question: When you hook up the 0-5 volt output from the wideband to the harness (at 6B), are you supposed to cut that wire at the harness... I;m guessing that wire goes out to the narrow band oxygen sensor.


BTW, this great information for not only me, but others who are going to install the AEM. The AEM forum is pretty weak as far as I could see.

 

[turbogate]

Yeah I just about have everything all wired up exept the Map signal wire and the wideband output.
Which brings me to this question: When you hook up the 0-5 volt output from the wideband to the harness (at 6B), are you supposed to cut that wire at the harness... I;m guessing that wire goes out to the narrow band oxygen sensor.


BTW, this great information for not only me, but others who are going to install the AEM. The AEM forum is pretty weak as far as I could see.

When this thread slows down, they should probably move it to the standalone section.

For the wideband, I'm using the uego. Since the 0-5 signal wire comes from the gauge itself (in cabin). I ran a new wire from the gauge to the O2 #1 pin on the ecu, replacing the stock O2 pin location. You could then either pull the stock O2 original wire/pin from the ecu and put it to rest peacefully somewhere in the area. Or you could move it to the O2 #2 pin, but I hear it's pretty useless once you have a standalone.

PS. I'm not sure if you got your AEM brand new, but it should have a set of extra pins for those situation where you want to use those extra I/Os of the Ecu etc

 

[drbowser3]

When this thread slows down, they should probably move it to the standalone section.

For the wideband, I'm using the uego. Since the 0-5 signal wire comes from the gauge itself (in cabin). I ran a new wire from the gauge to the O2 #1 pin on the ecu, replacing the stock O2 pin location. You could then either pull the stock O2 original wire/pin from the ecu and put it to rest peacefully somewhere in the area. Or you could move it to the O2 #2 pin, but I hear it's pretty useless once you have a standalone.

PS. I'm not sure if you got your AEM brand new, but it should have a set of extra pins for those situation where you want to use those extra I/Os of the Ecu etc

Yeah, I just used the factory O2 pin and wire just runs to my Uego instead of the stock O2 sensor which is long gone.

My AEM came with extra pins, but they were for Plug C, the additional plug for the other ins/out of the box.