I drive a 2011 2.5 srx 4x4 and being an srx it has no warning to remind you your headlights are on when you get out of the car. Knowing how murphy works I am bound to leave my headlights on and getting a dead battery somewhere in the middle of nowhere. So I decided to fit a buzzer. Here is my how to guide to how I did it.
Parts: -12v DC pcb mount buzzer that emits 85db (approx R21)
-diode that can deal with at least 30mA (approx R1.50)
-a piece of stripboard (not really needed but makes things neat)
-heatshrink to protect against vibration and to insulate
-some thin auto wires and a few spade connectors (it really only draws something like 30mA)
-insulation tape
-cable ties
Cost comes to approx R30. I bought the electronic components from Yebo electronics in Bellville.
Tools: -Soldering iron and solder
-side cutter
-needle nose pliers (useful to hold things together)
-whatever you need to access the required wiring in you vehicle (screwdrivers etc)
Step 1: Assembly
Solder the buzzer onto the stripboard. Then solder the diode onto the stripboard as well such that it connects on the negative side of the buzzer. Ensure that you put the diode right way around i.e. - "+" side of diode goes on "-" side of buzzer. Make sure to solder the diode leaving as much of the leg that you are soldering bare. You then cut this excess off as in the example below and solder it onto the stripboard on the "+"side of the buzzer thus making the positive connection pin. The other leg of the diode will make the negative pin. Cut a piece of heatshrink and put it over this assembly making sure to cut a hole for the buzzer and heat it. This should give you a insulated and compact little assembly. Example below.
Ok so you should have something similar to my example above now.
Step 2: Installation
In my vehicle I set it up as below. Disclaimer, this is a wiring diagram drawn in paint, poorly (I work with rocks
![Mr. Green :mrgreen:](./images/smilies/icon_mrgreen.gif)
I identified the wire running from the door switch and spliced the "-" for the buzzer into that where it passes the driver foot well making it easy to access. On the right hand side of my hilux dash I popped out the panel hosting the difflock switch. The difflock swith in my bakkie has a light that turns on with the headlights so I identified the power source for that and spliced the "+" line for the buzzer in here. After running both wires up into the dash and connecting the buzzer assembly I cable tied it to the wiring harness that is conveniently there. Example below:
Step 3: Test. Working 100% in my case and it only turns on when the driver door is open and the headlights are on. Video here: https://photos.google.com/share/AF1QipO ... VLYWtJOHV3
This should work on most cars however some modern cars could present issues to to computers complaining etc.