Garmin Descent G1 / G1 Solar setup guide

Also covers: Garmin Descent G1, Descent G1 Solar

Five-button dive watch (LIGHT, MENU·UP, DOWN, START·STOP, BACK) with Single-Gas, Multi-Gas, CCR, Gauge, Apnea and Apnea Hunt modes. Rechargeable; the G1 Solar also charges in sunlight. Tone and vibration alerts.

Buttons

Button	Where	What it does
`LIGHT`	left side, top	Turn on; backlight; hold for the controls menu (power off)
`MENU·UP`	left side, middle	Scroll; hold to open the main settings menu
`DOWN`	left side, bottom	Scroll; during a dive, step through the data screens
`START·STOP`	right side, top	Open the activity/dive list; choose a menu option; during a dive, open the dive menu
`BACK`	right side, bottom	Go back; hold to return to the watch face

Turn on / wake

Press LIGHT to turn the watch on. On first use, follow the on-screen setup and charge it.
PressLIGHT
Manual p. 1
Use UP and DOWN to scroll, START to choose an option and BACK to go back. Hold BACK to return to the watch face.
PressMENU·UPPressDOWNPressSTART·STOPPressBACK
Manual p. 1–2
Hold MENU (the UP button) to open the settings menu, where Dive Setup and System are found.
HoldMENU·UP
Manual p. 1–2
To turn the watch off, hold LIGHT to open the controls menu and select Power Off.
HoldLIGHTPressSTART·STOP
Manual p. 68
During a dive, hold functions do not work; press START to open the dive menu and BACK to leave it.
PressSTART·STOPPressBACK
Manual p. 1–2

Date and time

The manual describes no separate manual date entry; the date comes from the GPS or phone sync.

The watch sets the time and time zone itself when it gets GPS satellites or syncs with the paired phone app.
Manual p. 100
To change the format, hold MENU and select System > Time. Choose Time Format (12-hour, 24-hour or military) and Date Format.
HoldMENU·UPPressSTART·STOP
Manual p. 99
To set the time by hand, set Set Time to Manual, then use Time to adjust it.
PressSTART·STOP
Manual p. 99
After travel or for daylight saving time, use the sync option in System > Time to update the clock.
PressSTART·STOP
Manual p. 100

Units (m/ft, °C/°F)

The manual does not say which measurement type controls depth in dive modes; check the dive screen after changing it.

Hold MENU and select System > Format > Units.
HoldMENU·UPPressSTART·STOP
Manual p. 101
Select a measurement type, then select the unit (for example metric or statute).
PressSTART·STOP
Manual p. 101

Water type (salt/fresh)

The manual does not list the water type options; choose the one shown for your dive site. It also affects the gas calculator (p. 21).

Hold MENU and select Dive Setup > Water Type.
HoldMENU·UPPressSTART·STOP
Manual p. 6
Select the water type that matches your dive site.
PressSTART·STOP
Manual p. 6
You can also change it on the pre-dive screen: after choosing the dive mode, press UP to edit the dive settings.
PressMENU·UP
Manual p. 15

Dive mode (Air / Nitrox / Gauge)

From the watch face, press START and select a dive mode: Single-Gas, Multi-Gas, CCR, Gauge, Apnea or Apnea Hunt.
PressSTART·STOP
Manual p. 15
For one tank of air or nitrox choose Single-Gas. Gauge is a bottom timer only.
Manual p. 5
Press START until the main dive screen appears, then descend. The dive starts at 1.2 m (4 ft).
PressSTART·STOP
Manual p. 15
If you dive without choosing, the watch uses the last dive mode and its settings.
Manual p. 15
After a Gauge dive, only Gauge or Apnea mode can be used for 24 hours.
Manual p. 5
If you stay above a deco ceiling for more than 3 minutes, deco lockout blocks gas dives for 24 hours. Keep Deco Lockout on.
Manual p. 6

Nitrox O₂% and ppO₂ limit

The manual gives no default PO2 values and does not say that the O2 % resets by itself.

Hold MENU and select Dive Setup > Gases, then select the dive mode (Single-Gas).
HoldMENU·UPPressSTART·STOP
Manual p. 7
Select the first gas in the list (the bottom gas).
PressSTART·STOP
Manual p. 7
Select Oxygen and enter the O2 % of your analysed tank.
PressSTART·STOP
Manual p. 7
Select Helium and enter the helium %. For nitrox (no helium) this is 0. Press BACK when done.
PressSTART·STOPPressBACK
Manual p. 7
Set the MOD limit: Hold MENU, select Dive Setup > PO2 > MOD/Deco PO2, and enter the value your instructor gives you.
HoldMENU·UPPressSTART·STOP
Manual p. 8
PO2 Warning and PO2 Critical in the same menu set when the watch warns about high oxygen.
PressSTART·STOP
Manual p. 8

Conservatism / personal setting

The manual does not list the preset level names or values; check the choice on screen with your instructor.

Hold MENU and select Dive Setup > Conservatism, then choose a level.
HoldMENU·UPPressSTART·STOP
Manual p. 6
Higher conservatism gives shorter bottom times and longer ascents.
Manual p. 6
The Custom option lets you enter your own gradient factors. Do not use it unless you understand them.
Manual p. 6

Altitude

Not available on this computer

There is no altitude setting: the watch adjusts for altitude automatically with its barometric pressure sensor (p. 21).

Audible alarms (depth / time)

Hold MENU and select Dive Setup > Scuba Alerts.
HoldMENU·UPPressSTART·STOP
Manual p. 8
Select Add Alert, or select an existing alert to edit it, and turn it on.
PressSTART·STOP
Manual p. 8
For a Depth alert set the depth; for a Time alert set the time.
PressSTART·STOP
Manual p. 7 / 8
Select Sound and Vibe to choose a tone, vibration, or neither. Use Preview Alert to hear and see it.
PressSTART·STOP
Manual p. 8
Keep Silent Diving turned off; when on, it stops all tones and vibration during dives.
Manual p. 6
Built-in warnings include Approaching NDL (at 10 and 5 minutes left) and ascending faster than 9.1 m (30 ft) per minute.
Manual p. 23

Reading the log after a dive

From the watch face, press UP or DOWN to the dive log glance.
PressMENU·UPPressDOWN
Manual p. 20
Press START to see your most recent dive. To pick another dive, press DOWN, then START.
PressSTART·STOPPressDOWN
Manual p. 20
Press START and choose All Stats for the full details, or the depth and temperature graphs.
PressSTART·STOP
Manual p. 20
The surface interval glance shows CNS %, OTU, tissue load and no-fly time.
PressMENU·UPPressDOWN
Manual p. 19

Battery

To charge, pinch the charging clip, line it up with the contacts on the back and release, then plug in the USB cable. The screen shows the charge level.
Manual p. 102
Clean and dry the contacts before charging to prevent corrosion.
Manual p. 102
On the pre-dive screen, Battery is low appears below 20% and Battery critically low below 10%. Charge before diving.
Manual p. 23
Battery life depends on use; GPS mode lasts up to 26 hours (more on the Solar model with sunlight).
Manual p. 103
G1 Solar models also charge in sunlight; do not cover the screen with a sleeve.
Manual p. 102

What the main screen shows

The main dive screen shows your breathing gas, PO2 and ascent rate. Press DOWN or double-tap the watch for more screens and the dive compass.
PressDOWN
Manual p. 10
Ascent rate: good below 7.9 m (26 ft) per minute; moderately high up to 10.1 m (33 ft); too high above that.
Manual p. 10
The tissue load gauge fills as nitrogen builds up; at 100% the decompression stop gauge appears.
Manual p. 10
After a dive of at least 11 m (35 ft), ascend to 5 m (15 ft): the safety stop timer counts down when you are within 1 m (5 ft) of the stop depth.
Manual p. 18
If deco is needed, the stop depth and timer appear. Stay within 0.6 m (2 ft) of the stop until it clears.
Manual p. 19
At the surface the dive ends after the End Dive Delay, or press START and select Stop Dive.
PressSTART·STOP
Manual p. 15

Pre-dive check

Tick each item before you get in the water.

Correct dive mode chosen on the pre-dive screen (Single-Gas for air or one nitrox).
Bottom gas O2 % matches your analysed tank.
MOD/Deco PO2 is the value your instructor gave you.
Water type matches the dive site.
Conservatism is the level your instructor wants.
Depth and time alerts set; Silent Diving off.
No low-battery message on the pre-dive screen (charge above 20%).
Deco Lockout is on and no lockout is active.