© 2000 Directed Electronics, Inc. Vista, CA
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Interfacing with reversing polarity systems requires either two relays or a
451M
Door Lock Relay Satellite (not included).
It is crucial to identify the proper wires and locate the master switch to interface properly. Locate wires that
show voltage on lock and unlock. Cut one of the suspect wires and check operation of the locks from both
switches. If one switch loses operation in both directions and the other switch operates in one direction only,
you have located one of the target wires. The switch that lost all operation is the master switch. If one switch
works in both directions and the other switch works in only one direction, you have a Type A system. If both
switches still operate, but one or more doors have stopped responding entirely, you have cut a motor lead. Re-
connect it and continue to test for another wire. Once both wires have been located and the master switch has
been identified, cut both wires and interface as shown below.
IMPORTANT!
If these are not connected properly, you will send (+) 12 Volts directly to (-) ground,
possibly damaging the alarm or the factory switch.
type C: reversing polarity
