View Full Version : Unable to Connect CM849
nm2769
January 19th, 2016, 03:41 PM
I can not get my V2 to connect with V7.5 scanning tool. When I try to log my CM849 the V2 goes into pass through mode then just the yellow LED is lit. The V7.5 scanning tool shows that it is only connected to the V2 box not the ECU. I have selected CM849 before I attempt to connect. Same problem every time I try to connect. I tried to read the ECU with V8 and it gave an error that no ECU was found. I have OBDII dongle that has no issues connecting and sending data to my phone app so I know the OBDII port & wiring is ok. The one thing I can't verify is if a Cummins licensed V2 box is needed to scan. I have not purchased the Cummins tuning option yet. Do you need to purchased the Cummins upgrade to Scan?
ATPCummins
January 20th, 2016, 07:49 AM
You can data log without the Cummins upgrade, just cant flash. I would recommend being sure that your software is up to date and that you v2 is also up to date first.
nm2769
January 20th, 2016, 08:02 AM
You can data log without the Cummins upgrade, just cant flash. I would recommend being sure that your software is up to date and that you v2 is also up to date first.
I though that was the case that you can scan just not flash without upgrade. I am running the December 2015 release of the software and the V2 has the correct firmware for that software package.
I am not having any issues Reading, Scanning or Flashing my LS1B ECU. Thanks for your response.
ATPCummins
January 20th, 2016, 08:29 AM
What happens if you try to auto detect in V8? Will it recognize the ECM?
nm2769
January 20th, 2016, 08:35 AM
What happens if you try to auto detect in V8? Will it recognize the ECM?
No it will not recognize the ECM V8 pops up a screen that says No ECM Detected.
ATPCummins
January 20th, 2016, 08:50 AM
If you are able to communicate with and log other vehicles but not this one there must be something going on with the truck. If you plug in the v2 to the truck without it being plugged into your laptop does it light up (power to OBDII port)?
nm2769
January 20th, 2016, 09:20 AM
If you are able to communicate with and log other vehicles but not this one there must be something going on with the truck. If you plug in the v2 to the truck without it being plugged into your laptop does it light up (power to OBDII port)?
The problem I have with saying something is wrong with the truck is that a $15 OBDII scanner works perfectly. If I plug the V2 in without the computer it powers up fine. If i press any of the buttons on the V2 the screen stays lit but nothing is displayed and the V2 freezes none of the buttons do anything. Have to unplug it and then plug back in to get back the the home screen.
I'm going to format the V2 config file and do a clean install on the V2 and laptop and see if that helps.
nm2769
January 20th, 2016, 03:09 PM
I made some headway this evening but still isn't working 100%. I uninstalled the V7.5 & V8 software from the lap top. Used IObit to clean any remaining files & registry entries. I down loaded and installed the Dec software. Install went fine no issues. Formatted the V2 and checked firmware & updated config file. No problems here either. Works perfect on LS1B V7.5, V8, and BBX. I am able to connect the V7.5 scanner to the CM849 now. Scanning works as expected. V8 on the other hand will not recognize that it is connected to an ECM. When I press auto detect a few seconds later an EFILive window pops up and says that Flash Scan is not responding. Shortly after that the auto detect says only connected to V2 Flash Scan. V8 will not recognize the ECM in either Scan or Tune Tool. :confused:
nm2769
February 1st, 2016, 02:54 PM
V8 still wont connect to the ECM. Tried everything I know to do. Any suggestions? I want to purchase the Cummins license but not going to spend the money if it wont work.
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