This manual provides instructions for troubleshooting and repairing the engine control module (ECM) for trucks. It covers the 2010 emissions models of the CHU, CXU, GU, and TD.
This service manual details diagnostic trouble codes (DTCs) and troubleshooting for Mack’s 2010 emissions-compliant engine control modules (ECMs) for CHU, CXU, GU, and TD models. It covers OBD systems, module communication via SAE J1939, and ECM functions like fuel timing, EGR, turbo control, and derate modes. Diagnostic tools and scan tool requirements are specified, including restrictions on clearing DTCs via the instrument cluster.
The manual includes safety warnings, operational notes, and detailed sections on emission-critical ECUs, sensor monitoring, and fault logging. It also explains how to interpret MIL warnings and perform diagnostics using scan tools connected to the Serial Communication Port.
No, DTCs can no longer be cleared using the vehicle’s instrument cluster digital display and stalk switch control.
The use of a scan tool is necessary to perform diagnostic work as well as clearing any diagnostic trouble codes (DTCs).
The ECM, VECU, ACM, and other ECUs communicate via SAE J1939 (CAN1 or CAN2) data links to control engine and vehicle functions.