Cannot connect to ECU 95 Chevy 3500 16197427, help!

[n01tk]

Received my ALDL cable today. Setup laptop but no data. Following troubleshooting guide I determined my COM 1 is active. Tried using Hyperterminal as instructed in the troubleshooting guide. Still no data coming. Called Bob at ALDLcable. He suggested looking at M pin and common (A), should see 5vdc square wave. Could not see square wave, scope just showing a solid 5vdc? Does this data stream need to be turned on? I am not sure you would see data with a scope. Would think you would need a syn pulse to time scope scan. Reading the different forums individuals have had luck with Datamaster when everything else has failed. Confused, hoping for some suggestions.

[Six_Shooter]

What ADX file are you using?

I've installed a '7427 in my Grandfather's '71 pick up and haven't had issues connecting.

[n01tk]

Thanks for the reply. Just getting started. I am using the 31.adx and 31.ads. Could be files are not configured properly after download. If you look at my early post I did have some trouble with the extentions changing to .txt. Will let you know how I make out. Regards!

[Six_Shooter]

$31 may not be the mask that you have. Just FYI, there is also a $31 that is used in the turbo Regals and Grand Nationals as well. They are not the same, they just ended up being called the same by GM for some reason.

You will likely want the $0E definitions. I would assume that the 3500 has a 4L80E, and that is the code used in the '7427 with a 4L80E from what I have been able to find. $0D is another option, this is used with the 4L60E.

There are some really nice ones on moates.net fileman, made by a guy from fullsizechevy.com

[n01tk]

Thanks again for the reply six-shooter! I was using the older version of tunerpro and it didn't want to connect. I got up Saturday morning and thought I would take a new approach. I downloaded the RT version and re saved the def. files ($31) again from the TP site. This time being very careful to ensure the .ads and .xdf files are downloaded properly. ( had to go into properities and select tunerpro to be used to open them). After doing this the files came up with the proper logo, this gave me some confidence I was on the right road. I imported the .ads which changed to the newer format .adx. Connected up the ALDL to my PC and it showed DA Connected. Made my day! Was able to see live data but swamped with errors. At times the errors would come in at such a rate the data would freeze and I would have to disconnect and reconnect. Possibly the moades site would have a better operating version? Any more ideas? Regards

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[Six_Shooter]

The errors could be from using the wrong ADX, or just a timing issue in communication between the laptop and ECM.

Also you can download ADX files directly from the download section and not need to import an ADS file.

I'm not sure what you mean by "Downloaded the new RT version" the non RT version won't data log anyway.

[n01tk]

I am sorry for the confusion. I should have stated I downloaded the RT Version. Great idea, I will try using the .adx from the TP site. Let you know how I make out. Thanks for the continued support! Here is a picture of another jewel that I have owned for 25 years.

[n01tk]

Six-Shooter I tried your recomendation ( Thanx) but still getting errors. The connection is fine with the truck not running but soon as I turn it over the errors start. Could it be noise? Maybe a filter cap or shielding would help. How canI be sure when I have the proper def. files loaded. The RPM and other parameters appear to indicate OK with all the different def. files that I tried? You mentioned a fellow from Fullsizedchevy.com who posts on Moates, what his handle, I would like to read some of his posts. I am still educating myself and fining it enjoyable. Thanks for your help!

[Six_Shooter]

I didn't realize that there were no errors without the vehicle running. Are you using a power inverter with your laptop? I have heard of some people having issues, when using certain inverters.

Here is a thread on FSC.com: http://www.fullsizechevy.com/forum/gene ... files.html

[n01tk]

Hey Six-Shooter. Read some posts from fullsizedchevy.com. I may try using the modified $0E def. file mentioned. Sounds like it is a very versitile file. How can I look at the code to be really sure what my EPROM mask is? If I take the truck into my local dealer and have them scan it would they be able to see the mask? Looking for a way to be 100% sure of what EPROM mask is running in my truck.

[Six_Shooter]

Load an XDF, one that would be used with your ECM/PCM, and then find the "Mask ID" variable, most commonly found under "scalers", and see what the "value" is there. If it is "AA" it could be anything, since that is a checksum disable command, but this will not likely be seen, especially if you have read the bin off an EPROM.

Another way is to find what byte the MASK ID should be found at and open the bin in a hex editor, looking at that byte.

Also some research on your BCC can reveal what the actual code mask is.

I usually also looks at some tables and if they all look like what I would expect and other values all make sense then you can be pretty sure you have the correct XDF.

[n01tk]

I checked Eprom ID under scalars. I don't think I am opening up the location properly. It shows all zeros and states sixteen bits but doesn't appear active. I am connected to the ECU all data is active. When I go over to the left hand side and open scalars a long list appears. One of the scalars ( about half way down) is the Eprom ID. What do I do with it? I tried right and left mouse click. Doesn't show me whats in that location.