Beta RR 4T-250, Руководство по ремонту

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CHANGING THE WHEEL CIRCUMFERENCE,
UNIT AND NUMBER OF PULSES
The wheel circumference, the unit and the number of wheel
pulses can be altered only
when the vehicle is stationary .
Hold down the button while the TOD function is active until
the only information displayed is the circumference and all
the other segments are switched off. The different digits that
make up the wheel circumference figure can be altered in
succession from the most significant digit to the least signif-
icant digit. To shift the selection from one digit to the next (the
selected digit will blink with f = 1 Hz, Duty = 50%), press the
button for a short time.
NOTE: The wheel circumference can range from 1000 to
2500 mm in 1 mm steps. If the selected wheel circum-
ference is greater than 2500 mm, the system automati-
cally selects the default value (2
154
mm).
Once the wheel circumference has been adjusted, the unit
can be changed by holding the button down for about 3 sec-
onds while the least significant digit is active. This will bring
up the two abbreviations km/h and Mph and the selected unit
will blink for a few seconds (f = 1 Hz, Duty = 50%). The pa-
rameter is changed as described above.
When the unit is
changed, the TD and LAP parameters are both irre-
versibly deleted
.
Pressing the mode button for about 3 seconds when the se-
lected unit is active (the unit will blink with f = 1Hz, Duty =
50%), makes it possible to alter the number of wheel pulses.
This parameter indicates the number of pulses that the elec-
tronic transmission sends to the instruments for each wheel
turn, with a maximum of 6+ pulses for each wheel turn.
NOTE: The pulses may NOT be equally spaced.
Pressing the mode button for about 3 seconds while the cor-
responding value is selected will return the system to the
standard operating mode.
Installing the instrument panel
The default circumference value is 2
154
mm, the units for
speeds and distances are km/h and km respectively. The de-
fault setting for the number of pulses is 1 pulse per wheel
turn. To change any one of these parameters, use the pro-
cedure described in the previous paragraphs. When the in-
struments are first installed, the software version and pro-
duction date are displayed for about 2 seconds. Immediate-
ly after the display has been checked and the preset wheel
circumference and number of pulses per wheel turn have
been displayed, the system goes into standard operating
mode.
High power consumption functions
Given its high power consumption, the backlight unit and the
warning lights are operated only by the power supplied by
the vehicle. When no power is supplied (and the backup bat-
tery is activated) the backlighting is turned off and the warn-
ing lights disabled. This, however, does not prevent the in-
struments from working properly.
E 2 prom erasing procedure
When testing and checking an instrument, it is sometimes
useful to erase the E
2
prom memory. This is a procedure
which, in principle, is not intended for the user.
Workshop manual RR 4T - 250 - 400 - 450 - 525
To gain access to the procedure, follow these steps:
• Disconnect the instrument panel from the main battery and
the backup battery.
• Connect pin 5 of the input connector (unwired) to 12 V.
• Press the button.
• Restore the connection with the backup battery or the
main battery (if present).
The system will then erase all the data contained in the
E
2
prom and activate the default values (wheel circumfer-
ence 2
154
mm, speeds measured in km/h, distances mea-
sured km, 1 pulse per wheel turn). There is no way to re-
trieve the erased data.