AEM wont connect to my laptop
 

I'm using a Trendnet TUS9 USB to Serial adapter. Originally, when I first hooked everything up to the Miata, the EMS and laptop seemed to work well.

Although I never started the car, the AEM was able to communicate to my laptop through this set up; the cal was also downloaded successfully.

However, through the course of two weeks, something must have changed. During this time, I installed a GM MAP sensor, an AEM AIT kit, and PLX WB.

When I finally had time to load my base map tonight, I received the following prompts.

Offline.
Break Error.
Parity Error.
Offline.

This does not always occur, though, the prompts will sometimes only read as offline.

Thus, I believe this is a communication problem resulting from the serial/usb end of the equation. As Rafa mentioned, it is quite possible that I may have mixed up a wire. Though, upon reinspection, it appears everything is okay.

I have the AIT wired through the MAF sensor prongs.

The MAP is wired through the MAF ground, 5v source of the EGT sensor and 4F (directly into the AEM itself).

Though the wires are ready to be hooked into the AEM for the WB, I've been contemplating an insertion into the stock NBO2 plug; so, that is not even a variable here.

I apologize if anything is unclear in this post, it will be reread when I am more awake.

Please feel free to ask any addition questions; I will do my best to answer them.

Since I was the one who sold the AEM to Brian I feel compelled to try to assist him and given the fact that his issue is way over my head I'd like to ask for advice from any of the AEM gurus here (Jason and J_man please feel free to comment).

Thanks

Happened to me, turned out to be a bad serial cable.

I though so.

Many, many thanks Jason! :bowdown::bowdown::bowdown:

I have no experence with the aem in general but you should rechech all of your grounds and, make sure that the stuff you added was in the right input output location. If this does not work then i would get another cable and try that.

I had an extension USB cable hooked up and it would give me that error, took out the extension and everything was aok... so it could be the USB or the serial...

Thank you for all the advise, I will post my results.

An update:

I checked all the wiring again: specifically the grounds I disconnected when removing the oil pan and EGR pipe. Both of these were intact and well conducted.

In a move of disparity, I bought the other USB to serial adapter available in most stores: the Dynex's model. Of course, it was 10 dollars more and uses the same hardware as the original one.. Both use the "Prolific" driver, which I uninstalled and reinstalled using the newly supplied disk.

Again I am at a wall! Any other suggestions?

Thank you for all your help,

Brian

Brian,

What Windows version are you using?

What communication port are you using?

On AEM Pro, try to connect and go to:

"ECU" and then, "Communication Port". What does it say?

I am using Windows Vista.

The connection setting lists: COM7 Prolific USB to Serial Converter - or something to that effect.

I tried it on all three of my USB ports, adjusting to COM8 and 9 as needed.

Thanks for the questions Rafa.

Brian

I hate Vista.

Try changing the connection port to other options and see what happens.

Also; do you have another laptop you could use to test whether it is a communication problem?

The COM options rotate as I move the USB from port to port. I have three USB ports, so COM 7, 8 and 9 coorespond to each of them when active.

My sister's laptop has Windows 7; I'm in the process of installing the software on her computer now.

The AEM was hooked into my sister's laptop- the same errors occurred.

I suppose this is something to do with my car. Another thought I had was my battery, as it could be low from sitting. I hooked it up to my battery charger (on the 12v engine start setting) and the same error persisted.

I'm at a loss! Soon I wont have a commuter and I'll be up the creek.. ha ha

Does anyone near me (with a 94 or 95 miata) have the time to let me test this on their car? If I knew whether the AEM or my car was the problem this could be simplified a little.

Let me know if you have any other ideas!

Thanks,

Brian

Brian,

I really doubt this has anything to do with your car's battery.

Would it be too complicated for you to go back to the settings you had on the car 2 weeks ago?

I mean, without connecting the AIT, WB and MAP sensors.

This way we would know if this problem has anything to do with any of those.

Hot wire into the ECU reads a steady 11.6v

Confused by a little misinformation in another thread thread.

Would having double the voltage going through pin 1b be an issue?

1B has 24 volts going through it; that is the white and red wire. Is that normal? Also what are the ramifications if it isn't.

^^^ Led to my solution...

Figured it out! Thanks Miata.net