Cummins truck CM870 CM871 diagnosis by Inline 7 or Nexiq 2?

Here are tips and guides of those who are looking for a decent truck diagnostic tool for Cummins ISX CM870 and CM871 to read and clear fault codes and do calibration on his/her own.


Purpose: I would like to read codes, reset codes, and be able to calibrate the stupid turbo actuator myself.

Cummins trucks: I have a couple N14’s an 870 and a couple of 871’s


Question: What do I need for Cummins trucks


Professional suggestion:


Option 1: Nexiq USB link 2 + Insite


You need Insite, which comes in a few levels. You don’t really need the pro version, but it is nice to be able to update calibrations since they come out with new calibrations several times per year to fix minor issues. That wont be an issue on the N14’s, the 871’s are still having updates fairly regularly though. You’ll find that many diagnostics tell you to verify that the latest calibration is installed. All Insite levels require a subscription and have a yearly fee. You will not need an Incal subscription if you are only updating calibrations with newer versions of the same cal file, Insite will find and download new calibrations for the connected engine automatically as long as you have internet access.


On top of insite, you’ll need a diagnostic link adapter. I recommend the Nexiq 2 USB link (the genuine or a working china clone at a good price). It supports the most software and is the most popular one.

If you haven’t already, get a quick serve account set up, it free for up to 5 engines. Cummins will want it to set up Insite and if you do it first, it’ll speed up the process. You’ll just give them your username and skip the whole set up.


Option 2: Cummins Inline 7 + Insite


You need an inline adapter & the insite program. Both are available at your cummins distributor. We just replaced our adapter with the inline 7 adapter kit. Comes with all the wiring & plugs to connect to the engine or the connector in the cab. The insite program is available in different levels of functionality. I’m not sure what they are called now but distributor should be able to help you . Calibration changes require the use of incal which is a dealer only subscription.



IMPOTANT: Which option better? Inline 7 or Nexiq 2 USB Link ?


The two differences :
1. Inline 7 has wifi and bluetoot
h at the time, nexiq only one at a time.
2. Nexiq 2 has more protocols than Inline 7, for example the Inline 7 does not work with Hino, Toyota, Isuzu.

  1. Inline 7 runs slightly faster.

You can use inline 7 for everything from ddct to jpro and n14.

From old to new, it works great for programming real fast.

And sometimes cummins only like cummins adapters, like n14 m11 570 stuff like that in some users’experience at least

The final, Cummins Inline 7 wins!


But if you think it’s out of your budget, Inline 5 should be a good option.


Find a Chinese Inline 5. It will come with everything you need and works perfectly fine.

They are only $200 or so with all the programming for a knock off nexiq. They work perfect just never upgrade the drivers or you fry the module on the modem