Wiring Power Door Locks
William Ng - April 20, 2000


I have two methods to wire up power locks for anyone that needs the info:

One is for stand-alone locks with no alarm box...other takes an alarm into consideration.

1. Stand-Alone: No relays required.

Only a DPDT (double pole, double throw) high- current momentary swtch is needed. (but hard to find...try DigiKey, Jameco or any other mailorder electronics catalog)

The two leads (+/-) from each lock motor are wired in parallel.
They are connected the following way to the switch contacts:

 
 
            LOCK
          ________
         |        |
 motor + | __  __ | motor -   
         |        |
  +12V   | __  __ |  GND
         |        |
 motor - | __  __ | motor +
         |        |
         |________|

2. For alarm equipped cars...
(this method's applicable even if you don't have an alarm)

Need two SPDT Bosch style automotive relays. One SPDT momentary switch.

Once again the (+/-) lock motor leads are wired in parallel.


            
            (MOTOR+)                   (MOTOR-)
               |                          |
              30                         30
    GND--87a _____ 87----- +12V -----87 _____ 87a--GND
               |                          |
              _|_                        _|_
             |   |                      |   |
    GND---85-|___|-86-------o     o--86-|___|-85---GND
                            |     |
             RELAY1         |     |     RELAY2
                            |     |
    alarm output----------o.|     |
        lock              \       o----------alarm output
                    +12V---\      |             unlock
                            \_.___|
               
                    SPDT MOMENTARY SWITCH   
             
    
Capacitors can (should) also be wired in series in each (+) lead to each motor to prevent them from burnout in case the switch is push for too long.

If two switches are desired, just run the wires in parallel to each switch.