20
3 Wire Positive Pulse Systems
This power doorlock system is very similar to the 3 wire negative pulse system
except the vehicle's doorlock switches provide
(+)
12 volt positive pulses to
operate the doorlock relays/control unit.
Examine the wires on the back of the switch:
1) One wire will show
(+)
12 volts, regardless of the switch's position.
2) One wire will show
(+)
12 volts only when the switch is pushed to "lock".
3) One wire will show
(+)
12 volts only when the switch is pushed to "unlock".
Warning: The Positive pulse system can be easily confused with the 5-wire
Reversal rest at ground type system. This is due to the fact that both
systems show
(+)
12 volt pulses on the “Lock” & “Unlock” wires when the
vehicle’s switch is pressed respectively. It is critical to correctly identify
which system is present in the vehicle since if in an attempt to operate the
door locks
(+)
12 volts are pulsed into a Reversing polarity system, which
rests at ground, a “short” will occur.
3 main differences between a Positive pulse and a Reversal system:
1) In a Reversal type system the Lock & Unlock wires rest at a solid
ground, while in a Positive pulse system the Lock & Unlock wires show
partial ground which is feeding through the relay’s coils.
2) The switch in a Reversal system will have 5 wires, while the switch in a
Positive pulse system will have 3 wires.
3) A Positive pulse system has factory relays or a control unit, a Reversal
type system does not.
+
Door Lock Switch
DLP-P3 Blue Wire To
Switch Unlock Wire
DLP-P3 Green Wire To
Switch Lock Wire
Vehicle's Doorlock
Relay Control Unit
Unlock
Lock
D/U+
D/L+
DLP-P3 Connector
Plugs Into The
Control Unit
Doorlock
Actuators
USING OPTIONAL DLP-P3 INVERTER
