TM-9-2320-272-23-1
TRUCK, 5-TON, 6X6, M939, M939A1, AND M939A2 SERIES TRUCKS (DIESEL)
TECHNICAL MANUAL; FIELD MAINTENANCE MANUAL; VOLUME 1 OF 5
SEPTEMBER 2012
TM-9-2320-272-23-1 - Page 1100 of 1313
PRIMARY PRESSURE GAUGE READS NO PRESSURE, LOW PRESSURE, OR BUILDS TO NORMAL
OPERATING PRESSURE SLOWLY. SECONDARY PRESSURE GAUGE READS NORMAL (ENGINE IDLING,
BRAKE PEDAL NOT APPLIED) - Continued
STEP
2.
IS PRIMARY AIR PRESSURE GAUGE OPERATING PROPERLY?
a.
Stop engine and open all draincocks until brake system air pressure is vented.
b.
Close draincocks.
T0888DAA
Primary
Air Pressure
Gage Line
Primary
Air Pressure
Gage
Figure 2.
Primary Air Pressure Gauge.
c.
Disconnect air line from primary air pressure gauge. Refer to point to point schematics.
d.
Connect pressure gauge to disconnected air line.
e.
Start engine.
f.
Monitor air pressure on pressure gauge.
g.
If pressure gauge reads 90 psi after 5 minutes, primary air pressure gauge is not operating properly.
CONDITION/INDICATION
IS PRIMARY AIR PRESSURE GAUGE OPERATING PROPERLY?
DECISION
NO - Replace defective primary air pressure gauge (Volume 5, WP
0818). Go to Step (7) to verify problem is
solved.
YES - Go to Step (3).
TM 9-2320-272-23-1
0130
0130-3
Back to Top
