Vacuum Pump - Bosch ACS 561 Repair Instructions

Diagnostics and Testing
Vacuum Pump Troubleshooting
1. Check gauges for vacuum.
2. If pressure is over 0.7 kgf/cm
cover hoses.
3. If unit won't maintain vacuum, check high
and low side charge solenoids, hoses,
couplers, gauges, and other related com-
ponents, for leakage.
4. If there is no pressure on the gauges and
the display says Pressure Exists, enter the
Service Menu and verify low side inlet trans-
ducer reading. If it is reading pressure where
none exists, replace transducer. If replacing
the transducer doesn't correct the reading,
replace the control board.
5. If the compressor is not running or appears
to be running poorly, refer to Vacuum Pump
Does Not Run.
Figure 2-2. Vacuum Pump Assembly
SP00D00517 2018-07-11

Vacuum Pump

Vacuum Pump Does Not Run
1. Check for proper power source, circuit
(10 psi), re- breaker, and electrical connectors for dam-
2
age or corrosion. Replace or repair as
required.
2. Connect the unit power cable directly to the
power source. Do not use an extension cord.
3. Check for 230 Volts at the vacuum pump
connector, pins 2 and 3.
• If voltage is present, replace vacuum
• If voltage is not present, continue to next
4. Check for 230 Volts from the power board
on connector P4 pins 3 and 4.
• If voltage is present, check wiring be-
5. Use the output test and verify fan operation.
• If the fan is not functioning, check/verify
• If the fan is functioning, replace the power
• If voltage is not present, replace the
6. Perform functional check.
42
ACS 561 Service Manual
pump assembly.
step.
When checking voltage to the vacuum
pump it is normal to read low voltage at
the connector when it's disconnected
and the power to the vacuum pump is off.
tween the power board and the vacuum
pump. Repair as needed.
wiring, switches, and circuit breaker.
board.
power board.
If fan works, power is present at the
power board. The fan, vacuum pump,
and compressor use the same power
source.
Robert Bosch GmbH