GPS Secrets

There’s a lot of information to find — technical information, diagnostic information, and more.

Let’s begin our tour of the secrets of GPS units.

Hidden Secrets

Most electronic devices contain hidden diagnostic screens or setup menus that are used by the manufacturer to diagnose faults and possibly remedy them. GPS receivers are no different, but because of their limited number of buttons, numerous complicated keystrokes are often needed to access such menus so that users don’t accidentally find them.

You are unlikely to get any tech support for any of the undocumented features of your GPS unit, and these screens offer plenty of opportunity to cause problems and mess up your unit. Take care and don’t make any changes unless you are sure of what you are doing.

If you do make changes, take the following precautions:

 Make a note of the changes you are making — that includes any new settings and their original values.

 Don’t make too many changes at once. Better still, make one change at a time.

 If the unit appears worse after the change you made, undo the change immediately.

 If the unit doesn’t allow you to reverse a change, you will have to reset the device.

Garmin Secret Screens

I show you the secrets that are specific to GPS units from Garmin. Icover the older units, including the GPS III and III+, all the way up to the modern eTrex and Geko lines. I also include some specialized units, such as the Forerunner, which is designed to be worn on your wrist for hands-free outdoor activities, and the iQue, which is a combination GPS and Palm PDA.

Hard Resets

A hard reset wipes out all the data in your GPS and returns the unit to its initial factory settings. If you’re having trouble with your unit and a soft reset doesn’t help, a hard reset may be your only recourse.

Most of the hard reset sequences are complicated, to ensure that you don’t press them by accident. Some of these key combinations require an extra hand, or another person, to assist you.

To confuse the issue further, different models of GPS use different terms for a hard reset. Several models call it a master reset, for example.

The iQue 3600 is an exception. In this case, a hard reset wipes out all data on the iQue, but leaves any GPS-related data present.

Soft Resets

A soft reset is a way to erase all the data in your GPS’s memory and restart the system. Any settings you’ve changed are kept, but any waypoints, routes, or other data is deleted. You might want to do this when you’re having problems with your unit. A soft reset isn’t as destructive to the settings as a hard reset, so if you’re trying to fix your unit, you should try a soft reset first.

Only the Garmin iQue 3600 and Forerunner models have a soft reset feature. On the iQue, a soft reset deletes all the volatile memory, but any data saved in applications is retained.

Warm Resets

The warm reset feature is unique to the iQue 3600. It’s less dangerous than a soft reset, because it is the equivalent of booting a PC and reloading the applications. Memory management on handheld devices isn’t as good as on a desktop PC, and periodic warm resets help to solve problems and speed up operation. This type of reset can be useful for solving operating system issues with the unit. To perform a warm reset on the iQue, press RESET and SCROLL UP.

Full GPS Resets

The full reset is another function unique to the iQue. This reset wipes out all GPS data on the unit, but only GPS data. The PDA data remains intact. To perform a full reset on the iQue, press the RESET, ESC, and DateBook keys simultaneously.

Diagnostic Screens

The diagnostic screens on many GPS units give you access to an array of information about the unit. The screens available vary depending on which unit you have, but most of them will tell you the version of the firmware you’re running and the battery voltage. Some will also tell you the temperature of the unit.


Most units make the autolocate function a default feature. he autolocate feature deletes previous satellite data (the almanac) and downloads new data. It can sometime be very handy to force the GPS to download the almanac and “rediscover” where it is in the world. Some devices, such as the Garmin iQue 3600 and Geko, have an autolocate function that’s plainly accessible to the user. Others have the feature, but it’s hidden.

Magellan Secret Screens

Magellan is the other primary manufacturer of GPS units other than Garmin. Almost all GPS units come from one of these two manufacturers. The different types of Magellan units have very different hidden screens, so I discuss them in separate sections.

Magellan Meridian Series

One of the most popular ranges of Magellan GPS units is the Meridian. This handheld GPS receiver is bigger and heavier than the Garmin eTrex, but it has a larger, easier-to-read LCD screen.
There are two types of secret menu for the Meridian: boot time screens, which you activate when you switch on the unit, and a secret menu that you can access while the unit is already running.

Magellan 300/330

The Magellan 300 was probably one of the first GPS units to hit the mainstream GPS market — many were sold, and if you go to geocaching events you will see plenty still in use.