ELECTRONIC CONTROL SYSTEM ECM • The ECM uses sensor inputs to control the Injection Pressure Regulator (IPR), the EGR valve, the boost control solenoid, the glow plug relay and the inlet air heater relay. The ECM also shares sensor data with the IDM over communication links between the two modules. INLET AIR INLET AIR HEATER RELAY HEATER RELAY GLOW PLUG RELAY GLOW PLUG RELAY CONTROL MODULE CONTROL MODULE ASSEMBLY BRACKET ASSEMBLY BRACKET The IDM is mounted on brackets cast into the ECM. The ECM and IDM are then mounted with vibration isolator grommets to the control module assembly bracket.
The bracket is bolted to the truck's frame directly behind the passenger side of the cab and serves as the mounting point for the inlet air heater relay, the glow plug relay, and the Power Distribution Center (PDC). ECM ECM IDM • The Injector Drive Module (IDM) receives sensor information from the ECM over three communication links: the CAN 2 link, the CMPO circuit, and the CKPO circuit. The IDM uses this information to calculate injection timing and duration. The IDM controls injector operation through 48-volt signals to the twin injector coils. ECM X1 ECM X1 IDM X1 IDM X1 IDM X2 IDM X2 ECM X2 ECM X2 IDM X3 IDM X3 ECM X3 ECM X3 The ECM has four connectors.
The connectors are called X1 through X4 with ECM X1 being the top ECM connector as mounted on the truck. The IDM has three connectors with IDM X1 being the top connector as mounted on the truck. The ECM X1 and X2 connectors are for engine sensor inputs and X3 and X4 are for chassis inputs. The IDM X1 and X2 connectors are for injector operation and X3 is for chassis inputs and communication between the ECM and IDM. ECM X4 ECM X4 IDM IDM 23 International ® VT 275 V6 Engine