Coolant temperature, Trionic T7: Notes

The coolant temperature gauge gives the driver information on engine coolant temperature. The main instrument unit controls the coolant temperature gauge and supplies it with current.

The temperature sensor is connected to the Trionic T7 which continuously sends coolant temperature information on the bus. The main instrument unit obtains coolant temperature information via the bus.

Fig 1: Identifying Coolant Temperature Gauge And Trionic T7 (1 Of 2)

Courtesy of SAAB-SCANIA OF AMERICA, INC.

Fig 2: Identifying Coolant Temperature Gauge And Trionic T7

Courtesy of SAAB-SCANIA OF AMERICA, INC.

The coolant temperature gauge's scale is divided into 5 fixed breakpoints. The main instrument unit is programmed to move the gauge needle to the fixed breakpoints at certain specific temperatures to give a steady reading at normal coolant temperatures.

The following breakpoints are programmed in the main instrument unit (factory setting):

COOLANT TEMPERATURE SPECIFICATION

Gauge needle:	Coolant temperature
-into "blue" zone	30°C (fixed value)
-out of "blue" zone	50°C
-into "horizontal" position	80°C
-out of "horizontal" position	115°C
-into "red" zone	129°C
-out of "red" zone	130°C (fixed value)