TM 9-2320-365-20-2
2-1638
YES
NO
Is air present at relay
valve delivery port(s)?
A lack of air at delivery
port(s) of relay valve will
prevent air delivery to
service brake chambers
and cause rear brakes
not to apply.
Visual inspection
KNOWN INFO
TEST OPTIONS
REASON FOR QUESTION
10.
Front brakes OK.
Air tanks pressurized.
Supply air hose to foot
control valve OK.
Foot control valve OK.
Air hoses at cab floor OK.
Air hose to check valve OK.
Check valve OK.
Air hose to load sensing
valve OK.
Load sensing valve OK.
Air hose to control port of
relay valve OK.
Air hose to supply port
relay valve OK.
POSSIBLE PROBLEMS
Faulty relay valve.
Faulty air hoses to spring
brakes.
Faulty vent hose from
spring brake service
chamber.
Faulty spring brake
chamber.
Replace relay valve
(para 11-13).
i2. REAR BRAKES DO NOT APPLY (CONT)