DV673 (Hard Wiring) 

When making connections, the Poke & Wrap method, or Military Splice is the most efficient way to connect wires to factory wiring and is a Rosco standard for all installations. Be sure to insert (Separate) the wire before twisting it. This will avoid any intermittent power issues due to wires slipping off a connection. A zip tie is secured to the two wires after it is taped up to prevent a disconnection if the wires are pulled. Place your zip tie under the connection (blue arrow).

Wire Grounding: 

An installation with a loose ground connection or not screwed directly on a metal surface may cause an intermittent fault.

Vehicles with a loose ground can lose connection if the vehicle’s driving on rough roads such as potholes or speed bumps.

Scrape away paint if not a metal surface
Always use star washers to avoid contact resistance
Use a low clutch setting on your drill to prevent overturning

Approved Methods of Connecting Power 

Locate one of the following power sources in the vehicle:

Distribution fuse block Found in most Type A school buses
Ignition cylinder with spade connection Found in most Freightliner & Peterbilt trucks
Ring terminal battery adapters
Spare Aux wires Most international trucks have constant & ignition wires available from the factory for added electronics. Butt connectors can be used to crimp your connection securely
Bullet Connector Most Hino trucks have spare power wires with a factory bullet connector attached. Crimp the included male bullet connector to the DV6 power wire to make a secure connection

Alternative Hard Wire Connections:

1. Find the ignition (IGN) and power (BATT) wires, install the provided TTAP connectors (Red: 22-18 AWG, Blue: 16-14 AWG, Yellow: 12 AWG) onto wires with a pair of pliers. 
   (Fig. J)
   
   

   Fig. J

2. Connect the spade connectors of wires to TTAPs. (Fig. K)

   Fig. K

3. For ground wire (GND) wire installation with ring terminal, find an available metal surface and fasten the ground wire onto the surface using the provided self-tapping screw. (Fig. L)

   Fig. L

DV665 (OBD-II)

1. Find and remove the vehicle's female OBD-II connector from vehicle location.

2. Plug DV665 OBD-II male connector into the vehicle's female connector. (Fig. M)

   Fig. M

3. Install OBD-II female connector from DV665 into the original location of the vehicle female connector. (Fig. N)
   

   Fig. N

4. Find the ignition (IGN) wires, install the provided TTAP connectors (Red: 22-18 AWG, Blue: 16-14 AWG, Yellow: 12 AWG) onto wires with a pair of pliers. (Fig. J & Fig. K) 

DV672 (J1939) 

1. Find and remove the vehicle's male J1939 connector from its location.
2. Plug DV672 female J1939 connector into the vehicle's male connector. (Fig. O)
3. Install DV672 male J1939 connector into the original location of the vehicle's male connector. (Fig. P)
   
   

   Fig. O, Fig. P (inset)

   Find the ignition (IGN) wires, install the provided TTAP connectors (Red: 22-18 AWG, Blue: 16-14 AWG, Yellow: 12 AWG) onto wires with a pair of pliers. (Fig. J & Fig. K) 

Please note that one of the key benefits of using the DV665 and DV672 harnesses is simplified installation, along with the added functionality of harsh braking and harsh acceleration alerts for the end user.