Duct Leak
UNKNOWN

APU Valve Light
Indicates position of the APU Bleed valve disagrees with the position of the switch or the position called for by system logic.

Duct Press Indicator
Indicates Pressure in the left and right pneumatic Duct regardless of source.

Overheat Lights
Indicate associated engine HPSOV has been closed automatically due to a Bleed Air Overheat.

Bleed Lights
Indicate associated engine high stage and Bleed Air valves have automatically closed due to the engine Bleed Air temperature exceeding the maximum temperature limit.

Duct Leak Light
Indicate Leak in associated pneumatic Duct. Left light also indicates Leak in center pneumatic Duct.

ENG Switches

• ON - Allow associated Bleed valve to open when air pressure is available and system logic does not prevent opening.
• OFF - Close associated Bleed valve.

Engine Bleed Air OFF Lights
Indicate associated Engine Bleed valve is closed, either from turning switch off or from logic.

Isolation Valve Light
Indicates position of Isolation valve disagrees with switch position.

Isolation Switches
Opens or closes the L/C/R Isolation valve.