Table 8-2 Lighting/Power Pin Assignments; Table 8-3 Gtx 335 Power Control Inputs; Gtx 335 Power And Lighting Inputs; Gtx 335 Power Control Input - Garmin GTX 335 w GPS Installation Guidance

8.1.2

GTX 335 Power and Lighting Inputs

Power and lighting input requirements are recorded in this section. Refer to appendix B for power and
lighting interconnections.
• The power input pins accept 14/28 VDC.
AIRCRAFT POWER 2 is used to connect to an alternate power source.
Switched Power Out is a power source available for a remote digital altitude encoder device.
The GTX 335 unit can adjust to a 28 VDC, 14 VDC, or 5 VDC lighting bus.
The GTX 335 automatically adjust for ambient lighting conditions because of the photocell.
Pin Name
AV PWR 1
AV PWR 1
AV PWR 2
AV PWR 2
GROUND (power ground)
GROUND (power ground)
SW PWR OUT
GPS KEEP ALIVE
LTNG HI
LTNG LO
8.1.3

GTX 335 Power Control Input

The PWR CONFIG input sets the remote on/off feature. This is connected to ground for a remote unit
installation and not connected for a panel mount unit installation.
The PWR CONTROL input is dependent on the PWR CONFIG connection. This is used as a remote
power on/off control or to use the power auto on feature when the avionics master is energized.
Pin Name
PWR CONFIG
PWR CONTROL
8.1.4

GTX 335 Encoded Altitude Inputs

• Parallel Gray code altitude inputs are active if the voltage to ground is < 1.9 V or the resistance to
ground is < 375 Ω.
These inputs are inactive if the voltage to ground is 11-33 VDC.
190-00734-17
Rev. 1

Table 8-2 Lighting/Power Pin Assignments

P3251
Pin Number
21
42
61
62
20
41
39
60
19
40

Table 8-3 GTX 335 Power Control Inputs

Pin Number
I/O
I ALL
I ALL
I ALL
I ALL
I ALL
I ALL
O ALL
I ALL
I Panel Mount
I Panel Mount
I/O
59 I
38 I
GTX 335 w/GPS Installation Guidance
GTX Unit
Unit
P3251
P3251
Page 8-4