18
3 Wire Negative Pulse Systems
This power doorlock system is simplest of all doorlocking systems. A Negative
pulse system will have only three wires at the switch.
Examine the wires on the back of the switch:
1) One wire will show (-)ground, regardless of the switch's position.
2) One wire will show (-)ground only when the switch is pushed to "lock".
3) One wire will show (-)ground only when the switch is pushed to "unlock".
Note: The lock & unlock wires coming out of the switch operate the vehicle’s
doorlock relays or a control unit with on-board relays, therefore the lock &
unlock wires will read voltage, up to (+)12 volts, when the switch is at rest. The
correct connection point is between the switches and the relays.
The supplied 2-wire connector can be used to wire the system directly to the
vehicle’s Negative pulse system since only a (-)pulse output is required to
operate the vehicle’s on-board doorlocking relays. However if the vehicle’s
Negative pulse doorlocking system requires more than the 328i
2
’s 500ma
ground output, an optional interface must be used.
Doorlock
Actuators
Green Wire To Switch
Door Lock Wire
Door Lock
Switch
Blue Wire To Switch
Door Unlock Wire
Connector Plugs Into
The Control Unit
+
Vehicle's Doorlock
Relay Control Unit
Unlock
Lock
Ground
USING NEGATIVE OUTPUTS
