AEM Pinouts

[Tigchamp]

I am just going through all the pin conections that I need to do, to conect my 8 channel CDI, COP's & 2 EGT guages/sensors
I also need to conect My AEM Water Injection Monitor, all to a AEM series 2.
The WI Monitor needs a Ground (low side) output to pull timing or boost incase of a fault.
The series 2 AEM has 6 Low side drivers, can I use any of these and then asign the output in AEM Tuner.
Jeff:coo3l:

http://i817.photobucket.com/albums/zz93/Tigchamp/EMSPinouts002.jpg?t=1325613472

http://i817.photobucket.com/albums/zz93/Tigchamp/EMSPinouts001.jpg?t=1325613409

[Intropy]

If your WIM provides a low-side output ("switched ground", "pull-to-ground", etc) then you connect it to one of the EMS's spare switched input pins. Then you assign the option you want to that switch. E.g., you might assign Boost Switch Input to Switch 6 Gnd=On and hook it to pin 114. (Just going by your picture, no idea if that documentation is actually correct).

Further confusing the issue is that yes, with the Series 2 you can also use the low-side outputs as switched inputs. Only use ground switches, never connect 12v to your LS drivers! If you need to use a 12v / high-side signal to activate a LS pin, use a relay.

[Tigchamp]

So You are saying, Firstly use a switched input on the EMS.
But that I can also use a spare ground output.
Thanks, Jeff

[Intropy]

So You are saying, Firstly use a switched input on the EMS.
But that I can also use a spare ground output.
Thanks, Jeff

Right, use a switched input. That's their sole purpose. You can also use a LS driver, but there's no reason to do so unless you run out of inputs.

[Tigchamp]

Many thanks,
I dont know if you have read my build thread (in the sig) but I have two fans mounted on my SMIC's can I use the same method and have them switched on at a given AIT?
Jeff

[Intropy]

Not exactly. First, this is an output function, so in this case you want to use an LS driver that grounds a relay for your SMIC fans.

It's not quite that easy though. At the risk of getting too in-depth: the AEM has some limitations, one of which is that you can't just arbitrarily assign conditions to output drivers. For "general purpose" outputs, you're stuck with the parameters they provide, which are RPM, Load, TPS, Road Speed, and Coolant Temp. So you can say things like, "Activate this pin when RPM > 6000 and Load > 10", but not "Activate when AIT > 150".

For your purposes that's probably fine, since high AITs are pretty much going to directly correspond with high load, RPM, and/or coolant temp.

[mb3000]

Quick question, sorry about the thread hijack.

On the S2 installed on a 1g I was unable to find a high side output to run my fans off of, using this guide:
EMS to Control Electric Fans with High Side Output and Relay (http://forum.aempower.com/forum/index.php?topic=25999.0)

Although that was written for the original ems, I had assumed it was good. Would it be possible to use a spare low side driver with same relay shown in the write up?

[Intropy]

Of course, that's how you should do it. LS driver pulling to ground to activate your fan relay. The series 2 operates the radiator fans plug-and-play, right out of the box, using the stock wiring though. Any particular reason you're changing it up?

[mb3000]

Of course, that's how you should do it. LS driver pulling to ground to activate your fan relay. The series 2 operates the radiator fans plug-and-play, right out of the box, using the stock wiring though. Any particular reason you're changing it up?

First generation main fan isn't controlled by the ECU, and as a result isn't controlled by the S2.

[Intropy]

First generation main fan isn't controlled by the ECU, and as a result isn't controlled by the S2.

Ah OK. I don't own a first gen, obviously. :)

[mb3000]

Ah OK. I don't own a first gen, obviously. :)

Lucky bastard :p

[Tigchamp]

Not exactly. First, this is an output function, so in this case you want to use an LS driver that grounds a relay for your SMIC fans.

It's not quite that easy though. At the risk of getting too in-depth: the AEM has some limitations, one of which is that you can't just arbitrarily assign conditions to output drivers. For "general purpose" outputs, you're stuck with the parameters they provide, which are RPM, Load, TPS, Road Speed, and Coolant Temp. So you can say things like, "Activate this pin when RPM > 6000 and Load > 10", but not "Activate when AIT > 150".

For your purposes that's probably fine, since high AITs are pretty much going to directly correspond with high load, RPM, and/or coolant temp.

Thanks for Your answer.
In this instance I would probably be left with RPM or road speed, as the main reason for the fans would be whilst at idle to 1500 revs to stop heat soak whilst stationary or driving slow, as unlike a FMIC there will be no engine cooling or AC fan to draw cool air through the intercoolers.
Jeff

[Tigchamp]

Not exactly. First, this is an output function, so in this case you want to use an LS driver that grounds a relay for your SMIC fans.

It's not quite that easy though. At the risk of getting too in-depth: the AEM has some limitations, one of which is that you can't just arbitrarily assign conditions to output drivers. For "general purpose" outputs, you're stuck with the parameters they provide, which are RPM, Load, TPS, Road Speed, and Coolant Temp. So you can say things like, "Activate this pin when RPM > 6000 and Load > 10", but not "Activate when AIT > 150".

For your purposes that's probably fine, since high AITs are pretty much going to directly correspond with high load, RPM, and/or coolant temp.

So for this I would conect a LS Ground output to the ground terminal of a relay to switch on the fans?
There are a few available LS, Output, switched ground 1.5A, would this be the corect ones to use?
Does the amount of current being drawn from the relay affect the ground in any way?
Jeff

[Intropy]

Yes, you connect the LS output to the relay ground (the coil ground, obviously). You should never exceed 1.5A, which you won't because all you're hooking up is a relay.

[Tigchamp]

Yes, you connect the LS output to the relay ground (the coil ground, obviously). You should never exceed 1.5A, which you won't because all you're hooking up is a relay.

Thanks for Your help, I have just spent the day figuring out all the pin outs for the CDI & COPS, two EGT sensors & the WI, this should be the final conection that I need to make, Phew!
Jeff

[Tigchamp]

Questions dont get any more basic, and probably more important.
I am not convinced that I understand: "As viewed from end of EMS"
This is the "C" plug, is the top right pin as you see it, 80 or 85? (91-93)http://i817.photobucket.com/albums/zz93/Tigchamp/001.jpg

http://i817.photobucket.com/albums/zz93/Tigchamp/EMSPinouts001.jpg

[J. Fast]

[QUOTE=Tigchamp;152262]Questions dont get any more basic, and probably more important.
I am not convinced that I understand: "As viewed from end of EMS"
This is the "C" plug, is the top right pin as you see it, 80 or 85? (91-93)http://i817.photobucket.com/albums/zz93/Tigchamp/001.jpg


Top right pin is pin # 80. When you plug it into the EMS that will be on the top left.

[Tigchamp]

Thanks, Matey.
That means that I have done it right.
I keep convincing myself that it is right then the next minute I doubt myself LOL
Jeff

[fastfalcon94]

Bumping an old thread because it's the only thing useful I can find on here about it. Did you get any of the Low Side or High Side pins working? I need v2 aem to trigger a relay (it can either use high side or low side, doesn't matter) under a certain boost condition. This is for a 94 vr4. AEM only lists pin 43 as being HS#4 which is the only high side listed. My 94 vr4 does not have a wire at this location. I tried adding one from a spare ecu pigtail I had but it's not working. I configured the output to "General Purpose" and set it to activate with TPS at least 10% for testing purposes. I enabled the pin. In AEM I can monitor it and see HS#4 activating if I press on the gas pedal. But voltage measured at pin 43 is in mV. It's not getting 12volts like it should. I think the aem diagram is wrong.

So I went through some other potential pins, and I can't come up with anything. The only wire that was actually present and available for me to use was the maf reset. However I tested that and it doesn't see ground at all when a condition is met. Again I think the aem pin out diagram is not correct. If either of you got any output working, if you could let me know the pin I would really appreciate it.

LS# 11 - fuel pump can't use this
LS# 4 - evap can't use this
LS# 8 - maf reset. Wire is here, but tested it and does not force continuity to ground when conditions are met
LS# 9 - rad fan high can't use this
LS# 2 - rad fan low can't use this
LS# 6 - a/c switch can't use this
LS# 10 - Check Engine light can't use this
LS# 1 is pin 39, no wire on factory 94 vr4 harness here
HS# 4 no wire on factory harness here, still tried wiring it up, doesn't get 12v when condition is met
LS# 3 is pin 51, no wire on factory 94 vr4 harness here
LS# 5 is pin 55, no wire on factory 94 vr4 harness here
LS# 12 - ac clutch slip input can't use this
Injector 11 is pin 60 no wire here on factory 94 vr4 harness
injector 7 is pin 46 no wire here on factory 94 vr4 harness

Thanks - Charlie