Diagnose
Status September 2003 (EvoBus-Service / AFT)
Page: 62 of 83
4.1.18
Charge-air temperature
The charge-air temperature is calculated every 40 ms. The calculated temperature is smoothed with a
low-pass filter. The characteristic curve of the charge-air temperature sensor is stored in the engine data
record. If the voltage of the charge-air temperature sensor is above 4.95 V or below 0.20 V for more than
2 seconds, then the event "Fault measuring range exceeded or dropped below" is detected and the fault
code 1215 or 1216 is entered. The substitute value of 40 °C is then used as the charge-air temperature.
If the fault debouncing time has not yet expired, however the voltage value is outside the limits, the last
charge-air temperature calculated under valid conditions is retained. In the case of a fault, both the
measured value of the charge-air temperature and the air mass calculated from it are set on the CAN to
"Signal not available".
Characteristic curve: Charge-air temperature sensor
SEN - T charge-air: sensor code
Charge-air temperature [°C] = f(Sensor voltage [V])
C
ahr
ge air
temp
er
atur
e
Voltage
