ELECTRICAL TROUBLESHOOTING
TM 5-3805-263-14&P-3
INDIVIDUAL CIRCUIT DESCRIPTION
B. Brake Pressure
The brake air pressure circuit is activated by two normally open 9G8009 Pressure
Switches. The switches are normally open and are activated by air pressure. The
switches are closed if air pressure is above about 75 psi (520 kPa). If air pressure
falls below about 65 psi (450 kPa), the switches open and the brake pressure
indicator on the panel flashes ON and OFF. The operator panel also sends current to
make the master fault light flash ON and OFF, and if fuel pressure switch is open
(engine running) sends current to activate the fault alarm.
The brake pressure circuit connects to contact 8 of the operator panel. Contact
11 of the operator panel goes to the master fault light and contact 10 to the fault
alarm.
Figure 6. Brake Pressure Circuit
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