MT-121 & 131 - Device Placement
Device placement is the MOST IMPORTANT portion of the installation. If the device is placed in a poor location it could drastically reduce the effectiveness of the device. The best location for installation is beneath the front dash behind the radio or instrument cluster. The unit must be mounted with the label facing the bottom of the vehicle. The GPS antenna is located on the side opposite of the label. Metal will interfere with the GPS signal, the device should not be placed under any metal objects.
Plastic will not interfere with GPS signal
MT-121 & 131 - Wiring
Red - 12 Volt DC. The red wire must be connected to a constant 12-volt source from the vehicle to power the GPS unit. It is important that the 12 volt power source maintains 12 volts at all times.
Black - Ground. The black wire must be connected to a solid chassis ground uninhibited by paint or plastics. It is important that you do not use any floating grounds from the vehicles electrical system. Always connect the ground directly to the chassis body and secure with a factory bolt or aftermarket screw.
White - Ignition source. The white wire must be connected to a switched 12-volt source from the vehicle. This connection is used to monitor the engines on/off state. It is important that the switched 12-volt source drops to (0) zero with the ignition off and restores the switched 12-volts with ignition on.
Yellow - Positive input. Connect the yellow wire to a positive input source from your vehicle. This connection is optional and will alert yo when there is a voltage change on this connection. Example: Lights activated, tailgate used.
Green - Output. Connect the green wire to a desired output location on your vehicle. This connection is optional and will allow you to control an object in the vehicle from the web interface. When activated the green wire will become a GROUND activating your connected device. Example: ignition or fuel cut off.
MT-131 ONLY - Backup Battery
Connect the backup battery directly to the adaptor located on the wiring harness. The battery will power the device for up to 24 hours if the main power source is disconnected.