Definitely not an expert, but I found out that my Scangauge 2 would not clear a check engine light one time (think its when I had an APPS voltage out of limit code). Then I tried an Actron 9175 (not a low end model) which required some digging through the history to find and isolate the code. It would not clear it either. At the time, I had a Smarty programmer but it was boxed up because I was in the process of selling it and figured I would use one of the other less expensive units mentioned above instead. - No joy. .
Unpacked the Smarty and it instantly displayed the code and cleared it along with the check engine light easily.
That's when i started doing more research and found some slight little subtleties in the fine print of some product's literature, for example:
ScanGaugeII - Fequently Asked Questions
Notice how it shows. . "
Will the ScanGauge II be able to clear my
trouble codes and turn off my "Check Engine" light?
The ScanGauge II will clear the codes and turn off the check engine light on 99% of 1996 and newer vehicles.
It has been reported that it can not do this on some trouble codes in the Dodge vehicles. "
********
Compatibility list:
ScanGaugeII - Compatible Vehicle List
Notice for example. . "WORKS ON ALL EXCEPT: 2004. 5 through 2005 Dodge Diesel Trucks. " (On several years they specifically exclude Dodge Diesels - on 2000 vehicles it shows "Works on all vehicles" - Didn't on mine. . ?)
Here is another interesting thread from just searching out the word "Actron" in the search function on this site:
https://www.turbodieselregister.com...80-diagnostic-scan-tool-innova-vs-actron.html
Notice in the 2nd post. .
"Heavy duty pickups, above 8500GVW, such as our year model Dodge Diesels, are not required to be fully ODBII compliant and they are not fully ODBII compliant. "
********
At the time when I was doing the research on which unit to buy, there were several software type diagnostic tools available (don't recall the names without doing a major research project again), but 2 of them required you buy an "add-on package" to be able to read Dodge Cummins specific codes/parameters. This is where I started realizing that it would be easier for me to keep the smarty, as it appears to work well at reading & clearing codes quickly and easily.
********
Note: In my original post in this thread, I purposely didn't put any units down. I merely suggested a person do their homework before they buy, or make sure they can return the unit if it doesn't do everything you expected it to do. There are clear, defined reasons some of these compatibilities exist, like the newer year trucks use the "CAN" protocol, etc.
In reality, most of these units will probably work for 80 or more percent of the data you want/need, just know that our trucks may have some proprietary code in their software. Again, I'm not an expert, just passing along what I came across.