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Buschur COP/Dynatek Arc-2/AEM EMS wiring

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95eclipseSlow

15+ Year Contributor
131
2
Dec 10, 2007
Taylor, Michigan
I am super confused as to how to wire this combination up. I have looked at multiple diagrams from all kinds of different sources which only made me more confused.
My Buschur COP has three wires which do not have a connector on the end of them. Red- 12v, Green- 2&3, Yellow- 1&4. On the stock engine harness (97-99).
I have a coil connector plug that has three wires coming out of it, blue w/ red stripe, black w/ white stripe, blue w/ black stripe. I know that the black w/ white stripe is ignition power, blue w/ red stripe goes to that blue connector that is mounted on the firewall, and the blue w/ black stripe goes to the igniter power transistor connector.
The only wires coming out of the engine harness that are for the coils are the brown w/ red and black w/ blue coming from the igniter transistor connector pin 10 and 23 on ecu. I do not have a stock igniter or coil pack. I have an AEM EMS 1310 box.
I also have the plug n play harness from the dynatek arc-2. The harness has two connectors, one plugs into the COP (once it has a connector installed) the other plugs into the engine harness coil pack connector. I have that one connected and the only wire that does anything is the ignition power wire. One of the other wires goes to the blue connector on the firewall, the other goes to the igniter power transistor connector which is not connected to anything. The other connector is supposed to plug into the COP connector.
I also read something about jumpering JPC1 and JPC2 on the ems?? Can anyone help? I can provide any necessary pictures just let me know what you want to see.

Buschur COP

Red- 12v
Green- coil 2&3
Yellow- coil 1&4

Engine harness coilpack connector

Blue w/ red- blue connector on firewall which has nothing connected to it
Black w/ white- ignition power
Black w/ blue- igniter power transistor connector engine harness

Igniter transistor connection

Black w/ blue- coil 1&4 pin 10
Red w/ brown- coil 2&3 pin 23

Dynatek arc-2 harness

connector A to engine harness coilpack connector- coil 1 signal from ecu, coil 2 signal from ecu, ignition switched 12v

connector B to COP connector- output to coil 1, output to coil 2, coil ground

Is output to coil 1 supposed to mean the 1&4 pin 10 or 2&3 pin 23?
 
Okay lets make this a little more simple. The bold line is the first issue.

Buschur COP         Arc-2 Connector B (connects to oem coil pack or COP in my case)

Green - 2&3-------------------------White - Coil output 2
Yellow - 1&4-------------------------Blue - Coil output 1
Red - 12v------------------------Black - Ground

Why is it that a 12v and a ground are supposed to be connected?
 
The COP wiring instructions are for using a stock type ignition, which has 12V supplied to 1 side of the coil constantly, and the other side is switched to ground. This charges, then fires the coils by the switching to ground.

In that scheme, the 12V feed is common to both coils, and the actual coil fired is determined by the other wire.

The CDI does not supply 12V to the coils. They can be wired a bunch of different ways, but the way the ARC-2 is, it grounds one side of the coils constantly. Then the firing pulse of -540V(I think its negative, it was years since I worked with it) is sent through the other wire to the coil.

Buschur labeled his wires for installing into a normal ignition system. Ignore those instructions.

Now if you want to make your system easier to install, you could buy that triangular plug and add it to the Buschur COP, so that it all does plug in. JNZ, Extreme PSI, and a few others sell that. I think the JNZ thread on there forum might have some other good info for you.

I don't know why Buschur no longer includes the plug on his harnesses, I know he used to.
 
Thanks for the reply. I have a whole spare wiring harness so I can snag a triangular connector off of it. I figured that the 12v and ground thing was right I just was not 100% sure of how it worked. Now the next issue. I am not using the stock ignitor. The two signal wires from the ecu pin 10 and pin 23 both go to the connector for the ignitor. The stock coil pack connector has the power wire and the two other wires. Do I cut the two wires from the ignitor plug and run them to the coil pack connector where the two non-power wires are? The dynatek connector pin out is a switched 12v, coil 1 signal from ecu, and coil 2 signal from ecu for the plug that is supposed to connect to the stock coil pack connector. I have an AEM EMS 1310 and 6 bolt motor 97-99 harness if that matters.
 
Last edited:
Thanks for the reply. I have a whole spare wiring harness so I can snag a triangular connector off of it. I figured that the 12v and ground thing was right I just was not 100% sure of how it worked. Now the next issue. I am not using the stock ignitor. The two signal wires from the ecu pin 10 and pin 23 both go to the connector for the ignitor. The stock coil pack connector has the power wire and the two other wires. Do I cut the two wires from the ignitor plug and run them to the coil pack connector where the two non-power wires are? The dynatek connector pin out is a switched 12v, coil 1 signal from ecu, and coil 2 signal from ecu for the plug that is supposed to connect to the stock coil pack connector. I have an AEM EMS 1310 and 6 bolt motor 97-99 harness if that matters.

If you were planning on removing the ignitor, you shouldn't have gotten a plug in harness for the ARC-2. The ARC-2 plug in harness for the DSM has a tach adapter that is designed to work with the stock ignitor, creating a voltage spike that tricks the ignitor into thinking it is still plugged into the coils, and creating the right tach signal. Bypassing the ignitor would put that voltage spike right into the ECU. Leave the ignitor in, or get one of the universal install harnesses for the ARC-2. It should be cheaper than the plug in harness anyhow.

The plug in harness tach adapter makes it so that the ignitor still generates the right tach signal. So if you eliminate that, you are probably going to need to generate a tach signal too.

Why are you eliminating the ignitor?
 
I already have the pnp harness. Is there anyway I can just splice into the pnp harness? I was going to eliminate the ignitor as I do not currently have an ignitor and I also have no where to mount it. I do still have the connector and the wiring. Nothing on my setup is stock anymore. The dynatek does have a tach output wire. I found this in a different thread that you were active in:

Well, Just to give a little back ground. I deleted the ignitor and the wires coming from it. In doing so I didn't realize the Tach signal was Incorporated in those wires. I am using a AEM and Msd box. I wasn't getting any signal to the tach.

What I did was took the original wire coming from pin 58 and connected it to the original wire (white connector under radio) (i believe its pin 8) o to the tach. This is the way it is run in the original harness from Mitsubishi. And, what do you know, the tach is working correctly.
 
If you want to hack up the PNP harness, then just cut the tach adapter off it, and run the wires for the 2 coil inputs from the ignitor, directly to the 2 inputs on the ARC-2. Make sure to run the 12V that was going to the coils, to the activation wire on the ARC-2. This tells it to turn on with the ignition switch. You could still leave 1 of the triangular connectors on the harness to connect to the coils, or you can just hardwire the whole thing.

Don't forget to adjust the switch settings to account for the lack of ignitor. You are no longer triggering on the rising edge, instead it will trigger on the falling edge. Get that wrong and it will trigger very advanced.

Edit: You said you were running this with an MSD and no ignitor? I have no idea how, since that doesn't allow you to adjust for triggering on different edges. Maybe you already compensated for that inside the AEM by having it reverse the output levels? If so, you don't need to do anything to the ARC-2 switches and you should adjust them to the standard configuration for the Eclipse.
 
I do not have an actual PNP harness in my hands but the 95-99 DSM PNP harness from Dynatek doesn't seem to return any specific tach signal to the ignitor, only the three wires that would normally go from the ignitor to the coil pack (12V, Coil 1 and Coil 2). The ignitor generates the tach signal as a logical NAND of the two Coil signal. This is true for a 91-99 ignition

It actually does return a specific tach signal to the ignitor. It just does it on the same coil lines. It is a high voltage pulse fed back into the ignitor on the coil outputs from the ignitor. Without this high voltage pulse, the ignitor would not generate the tach signal. That is why with other CDI boxes you have to add on a tach adapter or use the CDI tach output.

The ignitor does not actually generate the tach signal as a logical NAND of the two coil signals on the input. It is actually generated from the feedback pulse of when the 2 coils fire.
 
If you want to hack up the PNP harness, then just cut the tach adapter off it, and run the wires for the 2 coil inputs from the ignitor, directly to the 2 inputs on the ARC-2. Make sure to run the 12V that was going to the coils, to the activation wire on the ARC-2. This tells it to turn on with the ignition switch. You could still leave 1 of the triangular connectors on the harness to connect to the coils, or you can just hardwire the whole thing.

Don't forget to adjust the switch settings to account for the lack of ignitor. You are no longer triggering on the rising edge, instead it will trigger on the falling edge. Get that wrong and it will trigger very advanced.

Edit: You said you were running this with an MSD and no ignitor? I have no idea how, since that doesn't allow you to adjust for triggering on different edges. Maybe you already compensated for that inside the AEM by having it reverse the output levels? If so, you don't need to do anything to the ARC-2 switches and you should adjust them to the standard configuration for the Eclipse.

For some reason I thought I had one of those male 3 pin triangular connectors, but I did not so I ordered one. I do not have an MSD that was from the excerpt of that other persons thread. Okay, so I am supposed to take pin 10 and pin 23 which are the two signal wires from the ignitor connector and cut them off of the connector. Next I should cut the two wires going to the engine harness side of the coil pack connector. I should then solder the the two ignitor wires into the two cut coil pack wires? The blue w/ red coming from the engine harness coil pack connector goes to the engine speed detection connector http://www.dsmtuners.com/forums/151542343-post53.html

Am I doing this right or am I supposed to just splice into the two wires coming from the engine harness coil pack connector? As far as the tach output it is a green wire with a butt connector on it. What do you mean cut the tach adapter off of it? There is also the issue of jumpers/transistors on the aem ems. Here is a link http://atdsm.com/pdf/COP.pdf

The bottom connector goes to the engine harness coil pack connector. The other connector goes to the COP connector.
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The connector that goes into the arc-2 box
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What is this black box? As you can see, the three wires (blue, white, black) coming from the COP connector do not go to the box but the rest do
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Entire harness, notice the three wires with the butt connectors, (tach sig, retard enable, clutch switch)
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Am I doing this right or am I supposed to just splice into the two wires coming from the engine harness coil pack connector? As far as the tach output it is a green wire with a butt connector on it. What do you mean cut the tach adapter off of it? There is also the issue of jumpers/transistors on the aem ems. Here is a link http://atdsm.com/pdf/COP.pdf

The bottom connector goes to the engine harness coil pack connector. The other connector goes to the COP connector.

What is this black box? As you can see, the three wires (blue, white, black) coming from the COP connector do not go to the box but the rest do

Entire harness, notice the three wires with the butt connectors, (tach sig, retard enable, clutch switch)

Looking at that ATDSM writeup, you can modify the AEM to drive the tach instead of the ignitor, so no wiring changes need to be made there. Follow their setup for the tach output, and that problem is solved.

Use their description of wiring from the AEM, and you will want to wire to the ARC-2 directly. The little black box in the ARC-2 harness is the part I said you shouldn't need anymore. Take the coil output signals from the AEM, wire them directly to the wires at the ARC-2 16 pin connector.

They have instructions for how to swap the output signal on the AEM, to work with the MSD. But since you have the ARC-2, you can just switch the edge select on the ARC-2, and you don't need to open up the AEM.

Does this clear it up?
 
Looking at that ATDSM writeup, you can modify the AEM to drive the tach instead of the ignitor, so no wiring changes need to be made there. Follow their setup for the tach output, and that problem is solved.

Use their description of wiring from the AEM, and you will want to wire to the ARC-2 directly. The little black box in the ARC-2 harness is the part I said you shouldn't need anymore. Take the coil output signals from the AEM, wire them directly to the wires at the ARC-2 16 pin connector.

They have instructions for how to swap the output signal on the AEM, to work with the MSD. But since you have the ARC-2, you can just switch the edge select on the ARC-2, and you don't need to open up the AEM.

Does this clear it up?

I understand to follow the directions in aempro for the tach output and that I do not have to open the aem box. The atdsm writeup says to wire coil trigger 1 of the ignition box to ecu pin 10. It also says to wire coil trigger 2 of the ignition box to ecu pin 23. What I am still unsure about is how I am wiring these two wires in. Just to get this clear, I am supposed splice the two wires pin 10 and 23 into the two wires on the engine harness coil pack connector? The pnp harness calls for the two signal wires from the ecu on the connector that goes to the engine harness coil pack plug. I do not know what I am supposed to do with pin 10 and 23 once they are cut from the ignitor connector. The whole engine detection connector is throwing me for a loop too. Am I keeping the black box? The switched 12v wire (orange) runs through that black box. I apologize for all of the questioning and clarification. I just want to get it right the first time so that I do not damage any of the components.

Which switches are supposed to be switched to the on position?
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For the pins 10 and 23, you are not going to wire them in at the 3 pin coil connector, you have to wire them directly in at the 16 pin connector on the ARC-2, to the coil 1 input and coil 2 input there.

If you cut the 3 wires going from the little black box tach adapter (near the black box), to the 16 pin ARC-2 connector, you can remove that box, and the 3 pin male connector which you won't be using. Now you have 3 cut wires going directly to the ARC-2. If you look at what they are wired to at that ARC-2 16 pin connector, it should be the coil 1 input, coil 2 input, and the coil 12V line.

In the ARC-2 harness, there are 3 wires that go direct from the 16 pin connector, out to the female 3 pin connector, and do not pass through the black box. Those wires will remain as is, and that is where you can plug in the coil.

Since you are cutting off the male connector, you could reuse that and attach it to your Buschur COP, but it sounds like you already ordered a connector.
 
Okay I got it now. The stock engine harness coil pack plug has the switched 12v wire along with the two other wires. It is okay to cut the switched 12v wire from the stock coil pack connector to use to connect to the orange 12v wire going to the 16 pin arc-2 connector right? Will that blue engine speed detection connector be affected at all by any of this as the stock engine harness coil pack connector will not be connected to anything anymore? Are the switches on the arc-2 box in the correct positions?
 
Okay I got it now. The stock engine harness coil pack plug has the switched 12v wire along with the two other wires. It is okay to cut the switched 12v wire from the stock coil pack connector to use to connect to the orange 12v wire going to the 16 pin arc-2 connector right? Will that blue engine speed detection connector be affected at all by any of this as the stock engine harness coil pack connector will not be connected to anything anymore? Are the switches on the arc-2 box in the correct positions?

That sounds correct. The blue engine speed detection connector will be basically removed from your circuit at this point.

The cam/crank switch may need to be on crank. I am not 100% certain about this. But as I remember, it determines whether it is firing 1/revolution(crank) or 1 time per 2 revolutions(cam). Since these fire wasted spark, I think it should be crank. Double check their instructions though. It will mainly affect your RPM calculations, and retard degrees calculation. So if you set the rev limit really low, you could check real quick to see if the cam/crank switch is set correctly or not.
 
That sounds correct. The blue engine speed detection connector will be basically removed from your circuit at this point.

The cam/crank switch may need to be on crank. I am not 100% certain about this. But as I remember, it determines whether it is firing 1/revolution(crank) or 1 time per 2 revolutions(cam). Since these fire wasted spark, I think it should be crank. Double check their instructions though. It will mainly affect your RPM calculations, and retard degrees calculation. So if you set the rev limit really low, you could check real quick to see if the cam/crank switch is set correctly or not.

According to the directions, the dip switches should be set as follows:

Rising Edge
Restrike -or- Single Spark
Crank Input

Looks like you were right about the crank input. Do you know whether rising edge is right or not for my setup? And the instructions were not very helpful on the restrike or single spark. Any idea as to which one of those it is supposed to be on? I do not have the luxury of experimenting as I am doing a completely fresh build. I got the car as a roller and the motor is brand new, never been fired. I am praying that all of the wiring/ems stuff is right so it fires up on the first crank.
 
Rising Edge would be correct if you still had your ignitor in there, as I mentioned earlier. Set it on falling edge since you bypassed the ignitor.

The single spark or restrike is just a question of whether or not it multisparks. Set it to single if you want to check your timing on this. The multispark could mess up the signal a timing light reads. Once you get everything sorted out, switch it to restrike.
 
Okay so single spark is only going to be used to set the base timing. Once that is set then I can put it on restrike and that is it. Thanks a lot for your help. I really appreciate it.
 
Glad to help. If it were me, I would probably try to check the timing with a light during cranking, just as a sanity check to make sure the coil1 and 2 weren't swapped, the trigger edges are correct, etc. That way you can try to eliminate some sources of issues, because it sounds like you did a lot of changes all at once.
 
I now have to wire up my auto trans harness. One of the wires needs to be tapped into the rpm (tach signal). Using the aem to generate the tach signal, which wire would I tap into? Would it still be pin 58, the white wire coming from the ptu, or the crank signal wire?
 
I would guess that you would want to hook it up ot the tach output from the AEM.

If you were hooking that up on a bone stock DSM, where would it go?
 
Pin 58, the white wire coming from the power transistor unit. Not sure what is used as a tach output from AEM

Pin 58, according to those other instructions. That is normally an input on the DSM ECU. Those other install instructions explained how to make it an output. So you should be able to just attach it to pin 58, once you follow the other instructions for setting it up as an output.
 
Okay I traced the white wire from ptu to the ecu and it goes to pin 58 and to the big white connector which I am assuming branches off into the gauge cluster. So the ecu will be emitting a tach output through this wire correct?
 
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