Where is the ACM On 2018 Granite? Please help

[Weezy]

Hello everyone. I’m having an issue with with no ACM communication on a 2018 mack granite. When driving on a farm check engine light comes on and codes that comes out is no communication to acm, nox sensor a and sensor b. I’m trying to look for the module and is playing hide and seek with me. Lol. Please Help!

[Joey Mack]

Im rusty, but isnt it behind the DEF tank?  

[fjh]

7 hours ago, Weezy said:

Hello everyone. I’m having an issue with with no ACM communication on a 2018 mack granite. When driving on a farm check engine light comes on and codes that comes out is no communication to acm, nox sensor a and sensor b. I’m trying to look for the module and is playing hide and seek with me. Lol. Please Help!

I am retired now ! However  as Joe mention  located behind the def tank low side ! The wiring on these is a always suspect quite often we had found breaks in the cluster of wire near the tank ! That said the sensors were also a pain usually had to be replaced as a pair for out of parameter codes ! NOT NO COMUNICATION codes!  

[Mackpro]

If the truck has a stand alone DEF tank then it’s mounted to the tank brackets facing towards the front of the truck. If the DEF tank in mounted directly to the fuel tank then it’s mounted high on the frame underneath the drivers side door. The cab suspension air bag often rubs the wires when mounted in that location. The fuse for the ACM is on to of the batteries and often loose battery cables are to blame 

Edited August 8, 2022 by Mackpro