The RSE circuit provides control to open or close the radiator shutters (energize or deenergize a solenoid).
Radiator shutters keep the engine warm during cold weather operation. When the ignition switch is ON,
power is available to the shutter solenoid.
The shutters will close when all of the following conditions exist:
• MAT is less than 37 °C (99 °F)
• IAT is less than 7 °C (45 °F)
• ECT is less than 80 °C (176 °F)
• No transmission retarder request is present
• No engine fan request is present
The shutters will open when any of the following conditions exist:
• MAT is greater than 60 °C (140 °F)
• IAT is greater than 12 °C (54 °F)
• ECT is greater than 87 °C (189 °F)
(Note: ECT is customer programmable)
• Transmission retarder request is present
• Engine fan request is present
The shutters will not close again until all closed conditions exist:
The ECM controls the shutter solenoid by providing a path to ground for the solenoid coil. When the shutters
need to be activated, Pin X3–22 is grounded from the ECM. When the shutters need to be deactivated, the
ground is removed from ECM Pin X3–22.
If all pin-point diagnostic tests are in specification, and the shutters are not operating in accordance with parameters, contact International® Technical Services.
Fault Detection / Management
An open or short to ground in the RSE control circuit can be detected by doing an on-demand Output
Circuit Check (OCC) during the KOEO Standard Test. When a fault is detected, a DTC will be set.