diagram for your 85 300sd...
Security
WIRE COLOR POLARITY LOCATION
Battery RED (+) IGNITION SWITCH HARNESS
Ignition 1 PINK/RED (+) OR PNK/BLK IGNITION SWITCH HARNESS
Starter 1 VIOLET/WHITE (+) OR VIO IN HARNESS GOING TO CONSOLE
All Door Trigger BROWN/GRAYF (-) ,BRN/GRY/BLK(-)R AT OEM ALARM RT FOOTWEL
Trunk Trigger BLACK/YELLOW (-) AT OEM ALARM MOD PASSENGER FOOTWELL
Alarm Disarm GREEN/YELLOW (-) AT OEM ALARM OR DRIVER'S KICK
Parking Lights GRAY/WHITE L (+) AND GRY R AT LIGHT SWITCH
ALSO (+) GRAY-DIODE ISOLATE
Convenience
WIRE COLOR POLARITY LOCATION
Headlights-Lo WHITE/YELLOW (+) AT LIGHT SWITCH
Remote Start
WIRE COLOR POLARITY LOCATION
Battery RED (+) IGNITION SWITCH HARNESS
Ignition 1 PINK/RED (+) OR PNK/BLK IGNITION SWITCH HARNESS
Ignition 2 PINK/YELLOW (+) IGNITION SWITCH HARNESS "2ND ACC"
Accessory 1 PINK/GREEN (+) IGNITION SWITCH HARNESS
Starter 1 VIOLET/WHITE (+) OR VIO IN HARNESS GOING TO CONSOLE
Anti-Theft Descript NONE
Tachometer BLACK (-) OR GRY/YEL (-) AT COIL LEFT INNER FENDER
Parking Lights GRAY/WHITE L (+) AND GRY R AT LIGHT SWITCH
ALSO (+) GRAY-DIODE ISOLATE
Brake Lights BLACK/RED (+) AT BRAKE SWITCH
Horn BLACK/YELLOW (-) AT STEERING COLUMN
Modules
WIRE LOCATION
Please select another category
Doorlocks/Windows
WIRE COLOR POLARITY LOCATION
Power Unlock GREEN OR BLUE (VAC) VACUUM DOOR LOCK SYSTEM "SEE TECH TIPS"
REQUIRES THREE SECOND LOCK PULSE
PowerLock GREEN OR BLUE (VAC) DRIVER'S KICK OR PUMP UNDER REAR SEAT
REQUIRES THREE SECOND LOCK PULSE
LF Window Up LF:GREEN
RF Window Up RF: BLACK/WHITE
LR Window Up LF:BLACK/PINK
RR Window Up RF: BLACK
Doorlock relays diagram for vacuum locks....
http://www.the12volt.com/doorlocks/page3.asp#vac
Alon