TM 9-2320-363-20-1
Display: 2 Solid Lights
Type: Loss of Deflate Signal
or Channel Deflate Loss
System Mode
Condition
Possible Causes*'
Inflate only
Inadequate deflate signal in
Plugged or restricted Pneumatic Control Unit vent line
the Pneumatic Control Unit
Faulty PCU relief valve
and Control lines
Faulty Pneumatic Control Unit
Poor ground connector to transducer
Faulty pressure transducer
*Possible causes are listed In order of likely occurrence.
Code Description
Deflate Signal code is logged. A "Channel Deflate Loss
or Loss of Deflate Signal" code indicates inadequate
deflate signal in the Pneumatic Control Unit (PCU) or
failure to sustain the signal in the control lines of a given
channel.
When a deflate is requested, the system drops the
control line pressure to a preset level which is
established by the PCUs relief valve.
If the pressure (typically 10-18 psi depending on the
PCU being used) cannot be maintained by the PCU,
either a Channel Deflate Loss or Loss of
This can be caused by:
Faulty Pneumatic Control Unit (relief
valve)
Plugged or restricted Pneumatic Control
Unit vent line
Line leak
To correctly diagnose the faulty component, connect the
Diagnostic Tool (see Page 3-92.16 for test equipment
and descriptions) and follow the procedure in the
Channel Deflate Loss or Loss of Deflate Signal
troubleshooting tree.
See "Troubleshooting Tips" on page 3-92.15 for general
guidelines on system diagnostics.
3-92.36 Change 3
