Help with MMCD

[BOOTZ]

I've followed the schematics on making your own cable to be able to log with MMCD and other logging software, but for some reason when I go to MMCD, Test, and press Read, beside DTC's, I get "ecu comm error" for both active and stored. I get 0hz in the bottom right corner and nothing comes up when I start the software. I have highlighted RPM and the box beside it and unpaused the software but still nothing, it says RPM on the bottom if i uncheck graph but no value comes up. Here is a picture of my cable, does anyone see something wrong with the cable compared to the schematics. I know my soldering skills are not the best but it looks like all the connections are good, there are no loose wires or anything. Any help would be appreciated to get this software working.

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[steve]

You'll have better luck if you don't ground the data line from the ECU.
Notice that you have both green wires connected to the same end of the resistor.
Hopefully you haven't blown the output driver on the ECU from that dead short.

Steve

 

[BOOTZ]

Thanks for the reply steve,

In the schematic it looks like both wires get connected to the resistor, does having both cables on the same end of the resistor really matter? I can't tell by looking at the schematic what is wrong with the way I have the cable wired.

If I blew the output driver on the ECU, then will I not be able to log and how did I create a short?

Should I try just connecting the data cable and not grounding pins 10 and 12?

 

[steve]

In the schematic it looks like both wires get connected to the resistor, does having both cables on the same end of the resistor really matter? I can't tell by looking at the schematic what is wrong with the way I have the cable wired.

Look at the schematic closely, they attach to different ends of the resistor. The ground wire that goes to pins 10 and 12 attaches to the end of the resistor that is connected to pin 5 on the DB9. Right now you have it attached to the same end that the data line goes to creating a short.

Steve

 

[BOOTZ]

good observation steve, I never would have noticed that.

I fixed the cable and gave it a shot and it worked!!! Now I just need to learn to read the log and figure out what everything means.

Thanks for the help steve, much appreciated.

 

[Spookcorleone]

This is abit different from MMCd but it has pretty much what is what. Will teach you pretty much what you are looking at, and why. A good read for someone that just got a datalogger.

http://www.hywell.org/plhelp/

Check it out.

You can also find updated verisons of the MMCd software so take a look around, sadly I lost that link.

 

[speedy13]

very good info.MODS,this should be a sticky or in the FAQ somewhere.

 

[BOOTZ]

thanks for the link Spookcorleone, very informative site.

speedy13, if I have some free time this week I will make a guide to making the cable and getting the software going. It might be useful for some people who are trying to make the cable and get the software going.

I find myself pushing my car a lot more since I got MMCD working, just to see if anything thing might be wrong with my car.