Displaying coolant temperature function - GF54.30-P-3020B
MODEL 208 as of 1.8.99, 210 as of 1.7.99
Networking
Signal flow
- The coolant temperature sensor (B11/4) changes its resistance depending on coolant temperature. (The sensor is an NTC resistance, i.e. the resistance decreases as temperature increases.)
- The resistance of the coolant temperature sensor (B11/4) is read in by the injection system control module (N3).
- The injection system control module (N3) converts the resistance values of the coolant temperature sensor (B11/4) into a temperature value .
- This temperature value is sent to the CAN/engine compartment by the injection system control module (N3).
- The instrument cluster (A1)
reads in this temperature value from the CAN/engine compartment and actuates the ECT gauge
(A1p1) accordingly. If necessary a warning message also
appears in the multifunction display (A1p13)
.
The ECT gauge (A1p1) is driven by a stepper motor .
Display of coolant temperature
- This display is a plateau display , i.e. the pointer stays on 95°C at temperatures between 95°C and 115°C. Temperatures in this range are not critical. The correct temperature is displayed again for temperatures of 116°C and over. This prevents the driver being unnecessarily disturbed by the display, e.g. at high outside temperature.
- The warning range
starts at 128°C
. From 128°C the coolant thermometer symbol and the warning message "COOLANT STOP, SWITCH OFF ENGINE"
is displayed in the multifunction display (A1p13). In addition a warning tone sounds.
If the engine fan is defective, the plateau characteristic is exited and values between 95°C and 115°C are also displayed.
Instrument cluster (IC), networking of components GF54.30-P-0002-06B Stepper motor, location/design/function GF54.30-P-3009A