My car didn't have a factory alarm, but the ones that did have an LED in the rev counter marked SECURITY. When my alarm was fitted (which was a complete bodge job from start to finish) they just cut a hole in my dashboard and glued the LED in place. I wasn't happy with it so I fitted a proper LED clip but it continued irritating me.Neil_turbo sent me a rev counter with a security LED in it for free which was very kind of him.
The standard LED is just red and the TOAD LED is bi-colour (red and green) which means it has an extra pin, so it's not just a straight swap. This is how I did it:Parts Required:
5mm bi-colour LED
(MUST BE COMMON ANODE - Maplin one is not suitable)Some form of 3 pin connector
(I scavenged plug + socket from a dead PC motherboard)New gauge:
Back of gauge, you can see the LED is a totally seperate board:
The white piece of plastic is just clipped to the main PCB in 2 places, so that comes off quite easily.
Once that's done the black wire from the LED board is attached to the main PCB with a push on connector which you can just pull off. After that the LED board has a single screw, and once off looks like this:
Took my electric solder sucker to it and removed all components:
Seeing as bi-colour LEDs are 3 pin, I was going to need a 3 pin connector to make the connection between the instrument cluster and the alarm loom.
The techies amongst you will recognise this:
It's a CPU fan connector from a motherboard.
And 30 seconds later...
I managed to fit the 3 pin LED into the board with a bit of bending of the red cathode pin.
The common anode and green cathode fit nicely into the board in place of the original LED's cathode and anode:
After that I soldered the black wire from the fan connector into the remaining PCB hole next to the LED
(the track for which runs to the anode pin on the LED), the yellow wire to the PCB hole into where the original red wire ran, and the new red wire into the hole opposite end of the board to the LED, left from where the diode was originally connected:
Screwed it back on
- all that's left is to punch a hole in the back of the instrument cluster to run the wire out of, and to snip the TOAD LED off and solder the white 3-pin connector on in its place. Simples!FYI the TOAD LED wire uses red for the red cathode, green for the green cathode and yellow for the common anode.
