Bosch Intellic EFAS-4.10, Руководство по ремонту

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Workshop Manual
Smart Tachograph EFAS-4.10/4.11
8.3.3 CAN-bus configuration of the auxiliary CAN expansion bus (CAN AUX)
This CAN bus is provided for additional functions such as connecting to remote data transfer equipment or to the DSRC module..
Configuration of the CAN bus and the role of certain CAN parameters is described separately in section 13.1.
8.3.4 Wake-up via CAN-bus (RDI=0xFD6B)
This parameter determines whether the tachograph can be activated by messages on the CAN interface with the ignition off
(i.e. from standby mode).
8.3.5 Source to reset the trip distance motion sensor (RDI=0xFD00)
The trip distance motion sensor can be reset either centrally from the instrument cluster via the CAN bus or directly via the
control keys (menu) on the tachograph. If control via the CAN bus is not required, resetting by tachograph should be enabled
with the parameter RDI=0xFD00. In the case of control by CAN bus, resetting from the tachograph menu should be prevented.
This is because the CAN message used to reset the trip meter in the tachograph also resets the trip information in other control
devices, and this cannot be guaranteed if the tachograph menu is used for resetting.
8.3.6 Source of lighting control (RDI=0xFD34)
The CAN bus allows EFAS to be connected to the central instrument lighting controller. In this case, the display and keypad
back-lighting are externally controlled. Control via the menu is not possible.
Alternatively, other vehicles use the light input A2 on the tachograph for lighting control. This type of control is also known as
a rheostat. If this is the case, the parameter RDI=0xFDA1 determines how the signal at connection A2 is used (see section 8.3.7).
With automatic detection, the device initially enables manual control until a valid “illumination” message is detected on the CAN
bus. Upon receipt of this message, the value for this parameter is automatically set to mode 1. If a status change is detected on
the light input A2, the value automatically switches to mode 0.
8.3.7 Operating mode of the input A2 for lighting control (RDI=0xFDA1)
This parameter RDI=0xFDA1 sets the operating mode of input A2 for controlling display and keypad illumination.
In mode 1, the tachograph adjusts the illumination depending on the light switch setting of the “Illuminations” CAN message
and the brightness levels specified for day and night operation. The brightness can be adjusted via the tachograph menu, as
described in the EFAS operating instructions.
In mode 2 the illumination intensity is set according to the analogue input signal at connector A2.
The mode 3 will selected for pulse-width modulated input signal at connector A2. The duty cycle of the input signal determines
the illumination intensity. If mode 3 is set, then parameter RDI=0xFDA2 must be set correspondingly (see section 8.3.8).
The mode 4 is intended for special (e.g. military) vehicles. Depending on the input signal to A2, illumination of the display and
keypad is completely shut off.
8.3.8 PWM configuration for lighting control
This parameter defines the control of the lighting when the input A2 is configured as an analogue PWM input. It defines the
minimum input voltage (control value = 0%) and the maximum expected input voltage (control value = 100%).
8.3.9 Factor for calculating the speed of the output shaft (RDI=0xF91E)
The tachograph calculates not only the current speed of the vehicle several times per second, but also the rotational speed
of the output shaft. EFAS supports an additional factor, known as the output shaft speed factor, which is used to calculate the
rotational speed of the output shaft and which is comparable to the k-factor used for the calculating the speed. The calculated
value is not always required by other control units in the vehicle. However, an incorrect value can cause problems with gear
selection in vehicles with an automatic transmission, for example.
The calculated value transmitted in the TCO1 message is not always required by other control units in the vehicle. An incorrectly
set value can, however, lead to problems in selecting the gear, e.g. in vehicles with automatic gearbox. Problems can also occur
with speed limiters, automatic cruise control, electronic brakes (Intarder, Retarder) and other automatic functions of the vehicle.
Unlike the k-factor, which varies according to tire size and thus requires calibration, the output shaft speed factor is a constant
and depends on the transmission type. It represents one thousand times the number of actual or effective teeth on the sonic
wheel. The factor that must be set for the vehicle may be indicated on the transmission’s type label. It should be noted that in