ACS 653, ACS 663 Service Manual
SP00D00624
2021-04-08
Robert Bosch GmbH
69
Electrical
Sensors and Transducers
The sensors and transducers provide the
input and feedback data needed to control the
operation of unit.
Sensors include:
1. Air Flow Sensor (AF):
senses whether the
unit cooling fan is operating (for ACS 663
only).
2. Scale Assembly:
weighs the refrigerant
in the ISV as a baseline for determining
the amount of refrigerant withdrawn from
the vehicle A/C system, the amount of
refrigerant added to the system, and how
much refrigerant is available in the ISV for
use.
3. ISV Tank Temperature (TT):
supplies the
temperature of the refrigerant stored in
the ISV for adjusting fluid weight based on
density.
4. Oil Drain Load Cell
: senses the weight of
the oil being drained (separated) from the
vehicle A/C system.
5. Refrigerant Identifier (ID)
: identifies
R1234yf refrigerant and tests refrigerant for
purity (internal on the ACS 663-RI; external
through the USB port on the ACS 663,
function disabled on ACS 653).
Transducers include:
1. Low-side Pressure (LSP):
measures the
pressure in the low side of the vehicle A/C
system.
2. Accumulator Pressure (AP):
measures
the pressure in the oil separator to ensure
proper oil separation from the refrigerant.
3. ISV Tank Pressure (TP):
measures the
pressure in the ISV tank.
Control Board Software Updating Methods
To access the operational capability of the
unit, or to provide an interface to an external
computer (or network), or to update the
software as required occasionally to keep the
unit current
.
See “Firmware update” in the
Setup Menu section.
Refer to Figure 3-4 (Sheets 1 through 4), for a
graphical representation of the interconnection
of the electrical components.
