11
CONNECTING THE DOME LIGHTS
The dome lights in the video monitor require three connections to the vehicle’s wiring. There are two common types of dome light circuits used,
positive switched systems or negative switched systems. Positive switched systems supply voltage to the interior lights to turn ON; negative
switched systems apply ground to illuminate the bulbs.
To determine which system you have to locate the wires at the dome light:
•
On a positive switched system, with all the doors closed and the lights out, both wires at the dome light will rest at ground. When the light is
activated, one of these wires will switch to +12 VDC. This is the vehicle’s switching wire.
•
On a negative switched system, with all the doors closed and the lights out, both wires at the dome light will rest at +12 VDC. When the light
is activated, one of these wires will switch to ground. This is the vehicle’s switching wire.
For positive switched systems, connect the Purple / Brown (Lamp Auto) wire to the vehicle’s switched wire. Then connect the Red / Black (Lamp
ON) wire to a fused constant 12 volt source and the Black / Red (Lamp Common) wire to a good ground. Positive switched systems are commonly
found on Ford vehicles.
For negative switched systems, connect the Purple / Brown (Lamp Auto) wire to the vehicle’s switched wire. Then connect the Red / Black (Lamp
On) wire to a good ground and the Black / Red (Lamp Common) wire to a fused constant 12 volt source. Negative switched systems are commonly
found on General Motors and import vehicles.
NOTE:
Some vehicles which incorporate transistorized control of the dome light circuit, such as the 1999 Dodge Caravan, may require that the
Purple / brown (Lamp Auto) wire be connected to the door pin switch wire, as the additional current draw of the monitor’s lights may not be
supported by the output of the vehicle’s body control computer.
After wiring the dome lights make sure the dome lights operate properly with doors opening and closing and that they are not always
on. Do not leave the dome lamp switch on the DVD overhead in ON position as this will drain the battery over time.
