TM 9-2320-272-10
2-3. CHASSIS CONTROLS AND INDICATORS (Contd)
Key
Item and Function
1
SELECTOR PANEL (M939A2 series vehicles) contains selectors for the four preset tire pressure modes and a
run-flat selector.
2
AMBER WARNING LIGHT (M939A2 series vehicles) flashes as an overspeed warning for cross-country and sand
tire pressure modes. It will stay lit when the emergency tire pressure mode is selected.
3
RUN FLAT (M939A2 series vehicles) selector causes the CTIS to check tire pressures every fifteen seconds.
4
ELECTRONIC CONTROL UNIT (ECU) (M9393A2 series vehicles) is the microprocessor in the CTIS. It is
contained in the selector panel housing.
5
EMERGENCY (EMER) (M939A2 series vehicles) tire pressure selector is used for operating the vehicle in
extreme terrain conditions where maximum traction is required.
6
SAND (M939A2 series vehicles) tire pressure selector is used for operating the vehicle in sand, snow, and mud.
7
CROSS-COUNTRY (X-C) (M939A2 series vehicles) tire pressure selector is used for operating the vehicle on
non-paved secondary roads and unimproved surfaces.
8
HIGHWAY (HWY) (M939A2 series vehicles) tire pressure selector is the normal operating modes of CTIS. The
highway mode is automatically set each time the engine is started.
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