Dakota Digital GPS-50-2 User Manual

mounting requirements on

the bottom of

page 6

.

GPS-50-2

GPS Speed and Bus Interface Module

IMPORTANT NOTE! When used to operate a cruise control, see the special

Connection for GPS
speed signal to other
electric speedometers.

GPS-50-2

GPS INTERFACE

OPTIONAL
ANTENNA

setup/status switchsetup/status switch

Connection to Dakota
Digital gauge system.

GPS-50-2

GPS INTERFACE

OPTIONAL
ANTENNA

Mount the outside
air temperature
sensor in the front
grill area or another
location that can get
good air flow while
the vehicle is being
driven.

www.dakotadigital.com

605-332-6513

ACC PWR

TEMP +

TEMP -

GROUND

SPEED 1

BATTERY

BIM I/O

SPEED 2

CRUISE

www.dakotadigital.com

605-332-6513

ACC PWR

TEMP +

TEMP -

GROUND

SPEED 1

BATTERY

BIM I/O

SPEED 2

CRUISE

BIM-xx-2
Power

Connect to main
chassis ground

+12V

CONSTANT BATTERY POWER

(fused 5 - 20 AMP max)

+12V

(fused 5 - 20 AMP max)

Standard speedometer output.

Connect to
BIM-xx-2
power/data
harness
if needed

Connect to
GPS-50-2

KEY ON POWER

AC speedometer output.

Cruise control speed output.

BIM-xx-1 adapter harness

BIM-xx-2 6 foot power/data harness

+12V

CONSTANT BATTERY POWER

(fused 5 - 20 AMP max)

Accessory power and
ground provided by BIM
power/data harness.

RED WIRE

BLACK WIRE

optional speed and
cruise control outputs.

BLACK WIRE

RED WIRE

optional SEN-15

+12V

KEY ON POWER

(fused 5 - 20 AMP max)

Connect to main
chassis ground

To gauge control box
or BIM-xx-1

Connect directly to another BIM-xx-2
or to the BIM-xx-1 adapter harness

& data
connectors

This Bus Interface Module can be used to provide an accurate speedometer signal with most manufacturers’ gauges and
also with a Dakota Digital system to provide speed, compass with air temp, clock, and altimeter functions. There are two
speedometer outputs to work with standard speedometers and a dedicated cruise control output. There are two interface
(I/O) ports on the module for use with a Dakota Digital gauge system. Either one can be connected to the gauge system
or to another module, allowing several units to be daisy chained together. Do not connect the I/O port to anything other
than a Dakota Digital gauge or BIM. Do not mount the module in the engine compartment; it should be mounted in interior
of the vehicle. Make sure the module is securely mounted and not hanging loose. It uses an internal acceleration
sensor which cannot accurately track the vehicle acceleration if it is loose.
The speed data does not use one of the 16 available bus ID’s like other Dakota Digital BIM units do. Speed data is
transmitted and updated every 0.1 second. The remaining data is sent one at a time in sequence along with any other
BIM modules present on the system.
The optional SEN-15 outside air temperature sensor can be connected when a Dakota Digital gauge system is connected
to provide a combination compass & air temperature readings together.
The GPS speed signal can be momentarily incorrect due to interference from overpasses, tunnels, and nearby structures.
To avoid this problem, the system stabilizes the speedometer reading by constantly comparing it with an internal
acceleration sensor. When the key is off, the system goes into a very low power standby mode and only occasionally
wakes up to update GPS readings so that it is ready to start operating as soon as the key is turned on.
The GPS-50-2 has an internal GPS antenna to directly receive GPS signals without the need for an external antenna. An
external antenna can optionally be added to enhance reception if the GPS-50-2 is mounted where GPS signals cannot
reach it. Contact Dakota Digital for part number and availability.

1 MAN #650519:B

Initial setup

Once the module is mounted securely and wired, there are a few internal tasks the GPS module will complete on its own.
First, the module needs time to acquire and track the satellites. This typically won’t work inside a steel building, so have
the vehicle outside to speed up the process. There is a dot in the upper right of the display that will be on steady or on
and flashing any time the key is on. The dot in the top center of the display will be on steady once it has gotten a GPS
satellite fix. The unit won’t operate until it gets a fix and this may take 1 – 15 minutes depending on various things. This
delay is only for the initial GPS fix. After this it will typically begin operating within a few seconds of turning the key on.
The second step is to let the internal acceleration sensor learn how it is mounted in the vehicle. You can mount it
securely in any position you want. When you are sitting still it learns which way is up. In order to learn which way is the
front of the vehicle you need to accelerate or decelerate on a straight stretch of road. Accelerate or decelerate for at least

2.5 seconds and make sure your speed changes by at least 10 mph. This procedure only needs to be done initially and
doesn’t need to be repeated unless you move the module to a different mounting location.

If you move it to a new mounting location or a different vehicle, enter the setup menu and select the rst option to speed
up learning the new mounting position.

Dakota Digital display data usage
The speed outputs can each be used in place of a separate transmission connection to the gauge control unit. The clock
is based on the accurate GPS time and only the hours need to be set to match it to your time zone. The compass
requires no setup or calibration for the vehicle and is accurate any time the vehicle is moving. The altimeter is calculated
from the GPS position data to give your current elevation. Each of these can be individually turned on or off.
The compass and altimeter may not display correctly unless the gauge control has the following firmware version or
higher:
VFD3: SE46

VFD3X: SE55
VHX: C VX04.009 (control box firmware must end in “.009” or higher)
D V***.006 (display firmware must end in “.006” or higher)

The compass, clock, and altimeter will be displayed in the message center.

Using speed from the GPS-50-2 without a BIM-01-x connected

• Make sure the BIM units are all connected to the gauge control box with the supplied BIM power/data cables.

• Hold the SW1 switch from the gauge system control box while turning the key on. The message display should

show SETUP.

• Release SW1. The message display should show SPEED.

• Press and hold SW1. The message display should show SENDER. Release SW1.

• Press and release SW1 until BUS is displayed.

• Press and release SW1 until DONE is displayed.

• Turn the key off.

• Next, press and hold the switch on the GPS-50-2 while turning the key on. The GPS-50-2 display should show

the current software revision.

• Release the switch. The display should show “-C-”.

• Press and hold the switch until “ - ” is displayed.

• Release the switch. The display should show “SPD”.

• Press and hold the switch until “ - ” is displayed.

• Release the switch. The display will show the current setting.

• Press and release the switch until “ON” is displayed.

• Press and hold the switch until “ - ” is displayed.

• Turn the key off.

2 MAN #650519:B

Using speed from the GPS-50-2 with a BIM-01-x connected

• Make sure the BIM units are all connected to the gauge control box with the supplied BIM power/data cables.

• Hold the SW1 switch from the gauge system control box while turning the key on. The message display should

show SETUP.

• Release SW1. The message display should show SPEED.

• Press and hold SW1. The message display should show SENDER. Release SW1.

• Press and release SW1 until NORMAL is displayed.

• Press and release SW1 until DONE is displayed.

• Turn the key off.

• Next, press and hold the switch on the GPS-50-2 while turning the key on. The GPS-50-2 display should show

the current software revision.

• Release the switch. The display should show ì-C-”.

• Press and hold the switch until “ - ” is displayed.

• Release the switch. The display should show “SPD”.

• Press and hold the switch until “ - ” is displayed.

• Release the switch. The display will show the current setting.

• Press and release the switch until “OFF” is displayed.

• Press and hold the switch until “ - ” is displayed.

• Turn the key off.

• Connect the GPS-50-2 SPEED 1 terminal to the gauge control box SPD SND terminal.

To set or change the GPS clock ID number and the time format:

• Hold the switch beside the GPS-50-2 terminal strip while turning the key on. The display will show the current
revision code while this is held.

• Release the switch. The display will show “-C-”.

• Press the switch and hold the switch until “ - ” is displayed.

• Release the switch. The BIM display will show “spd”.

• Press and release the switch until “ CL” is displayed.

• Press the switch and hold the switch until “ - ” is displayed.

• Release the switch. The display will show the current ID for the GPS clock.

• Press and release the switch to change the setting from 1-16 or OFF. OFF will prevent the GPS clock from being

displayed.

• Press and hold the switch to save the setting. The BIM display will show “12H” or “24H”.

• Release the switch. This is the current time format.

• Press and release the switch to change between 12 hour and 24 hour format.

• Press and hold the switch until “ - ” is displayed to save the settings.

• Turn the key off.

3 MAN #650519:B