a couple of people emailed me about how to use the security
led to light up when the J&S unit detects knock, so here you go...

1. you only need 3 parts: 1 3.5mm stereo plug, 1 LM3914 chip, and 1 220ohm resister.

2. Pull out the built-in security led and look for the orange wire.
This wire will cause the led to light up when shorted to ground.
You'll want to tap into this wire and route it to your J&S unit.
Note: this mod does not alter the security led functionality when the car is off...

3. wire up the 3 parts mentioned above using the following diagram:




4. the led will now light up for a brief period when the key is
first turn to the "on" position. This is the J&S unit doing it's
normal thing of lighting up the display on startup.

5. the led will light up anytime any cylinder is retarding.

enjoy,
rob

 

very neat! I havent really noticed, but is the security LED easily visible from the driver's seat position?

Cool idea!

 

This was my ery first thought, as the secuity led in the G is very visible (never seen the Z's). BUt, I really wanted the 10 LED display that shows the amount of retard, so i know how badly i am pinging. So, a good friend of mine, a member of the forum, will be building me the 10 LED display just like th eone sold by J&S as per J&S's provided schematics, and I will be integrating it flush into th eaft side of the a-pillar.

Gurgen

 

Gurgen,

What you see is actually the ENTIRE 10 led display.

Pins 10-18 are the other 9 led pins (unused in diagram).

To display all ten leds, buy a 10 segment led (about $2)
containing 3 red, 4 yellow, then three green.

So, for you DIY'ers, if you want a simple tool ($10) to
help setup the J&S or to monitor it, just add 1 more part
(2 bucks) to get a 10 led graph...

enjoy,
rob

ps. here's the led pin order

degree: 2', 4', 6', 8', 10', 12', 14', 16', 18', 20'
pin: 1, 18, 17, 16, 15, 14, 13, 12, 11, 10
color: green x 3, yellow x 4, red x 3

 

oh, forgot.

the previous 10 led display is fine to pullout every once in a while
for setup/testing, but if you want to mount it somewhere, then you may want it's brightness to dim/brighten in daylight/nighttime.

to do this, buy a photo-resisitor and put it in series with the 220 resister (total of 5 parts, still cheap).

enjoy,
rob

 

NICE~!

Very cool......