Table 3-10 Discrete Inputs - Garmin GTR 200B Installation Manual

3.6.5.4 Lighting Bus Interface Check
The display and bezel key backlighting on the GTR 200/200B can track an external lighting/dimmer bus
input and use it to vary the display and bezel key backlight levels accordingly. This check is only
applicable if Lighting Source (on the Lighting Setup Page,
verifies that the interface is connected correctly.
1. Refer to Section 3.6.4
2. Ensure the lighting bus input is set to its minimum setting.
3. Slowly vary the input lighting bus level. Verify that the display brightness tracks the lighting bus
setting. Continue to maximum brightness and verify proper operation.
3.6.5.5 Discrete Input Checkout
If one or both discrete inputs (Table 3-10) are connected, the wiring is checked using the following
procedure.
1. Refer to Section 3.6.4
2. While the momentary contact pushbutton(s) are not being pressed (inputs are not grounded), verify
the DISC 1 and DISC 2 check boxes are not checked. If one or both boxes is checked, the wiring
is likely the cause of the failure.
3. Activate the DISC 1 and/or DISC 2 input by pressing the associated momentary contact
pushbutton (inputs are grounded). Verify the appropriate checkbox is checked. If the checkbox is
not checked the wiring is likely the cause of the failure.
Pin Pin Name
2 DISC 1
22 DISC 2
190-01553-00
Rev. P
to select the Lighting Setup Page.
to select the Discrete Setup Page

Table 3-10 Discrete Inputs

Configurable discrete active low input 1
Configurable discrete active low input 2
Section 3.6.4.6) is set to 14V or 28V, and
(Section 3.6.4.5).
Description
GTR 200/200B Installation Manual
Page 3-17