Paccar Peterbilt 567 2021, Manual

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The Primary gauge indicates pressure in
the rear braking system:
Primary Air Pressure Gauge
The Secondary gauge indicates pressure
in the front braking system:
Secondary Air Pressure Gauge
The Primary and Secondary Air Pressure
gauges are shown in the Primary Gauges
View on the Digital Display.
18
At start-up, the Primary and Secondary Air
Pressure gauges may indicate red, and the
Low Air System Pressure alarm may sound
until the minimum operational pressure
setpoint of 65 psi (448 kPa) is reached.
1920
If the tanks are empty, this can take up to
two minutes. If these gauges
• Remain red
• Turn red
• Indicate below 65 psi (448 kPa)
Or the Low Air System Pressure Alarm
• Turns on
• Does not turn off
do not attempt to drive the vehicle until the
problem is found and fixed: system
pressure is too low for normal brake
operation.
NOTE
Park brakes lock up at 60 psi (414
kPa), the audible alarm will sound at
65 psi (448 kPa).
How to Check the Compressed Air
System for Leaks
WARNING
DO NOT operate the vehicle if leakage
in the air system is detected. Conduct
the following procedure and contact an
authorized dealer (or any other proper-
ly equipped service center) if a leak is
detected. Failure to check the brakes
or follow these procedures could
cause a system failure, increasing the
risk of an accident and may result in
personal injury, property damage, or
death.
Use this procedure to check the
compressed air system due to the
following:
• After maintenance
• When an air system component is
replaced
• When a leak is suspected
18 The model 520 Right-hand Stand-up uses additional physical gauges for Primary and Secondary Air Pressure.
19 The model 520 Right-hand Stand-up also indicates low air pressure using a warning light in the physical gauges.
20 The Low Air System Pressure alarm is not active when the engine is off.
MAINTENANCE - Air Gauges and Air Leaks
Y53-6126-1A1 (01/21) 237
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