Understanding the electronics of the keyless entry system

chimchim

iVTEC, do you?
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I already read about how to splice the old radio with a new one so you can keep your keyless entry system working in a 96-98 civic. Here's the info I can't seem to find:

I looked at the pinout definitions of the wiring harness and it only includes: +12v batt, +12v ignition, GND, FR+- . FL+-, RR+-, RL+-, auto antenna, and dash dimmer.

Where did they piggy back the keyless entry signals?

So I theorize that the keyless entry works like this: encoded packets are sent by the FOB and are received by the antenna of the OEM deck. (Apparently, the OEM deck doesn't need to be attached to the antenna since the frequency range of the remote can be sensed in the close proximity of the car with an internal antenna.) The deck keyless circuitry, which is powered by the +12v batt and GND, are essentially always on (but don't suck up much power). The FOB packets are decoded and the three possible signals are generated: lock, unlock, and sound the horn panic. Somehow these "signals" are sent to the ECU which performs the lock, unlock, and horn beeping. BUT HOW ARE THESE SIGNALS SENT?

Is there another wiring harness on the OEM deck that has nothing to do with the new deck? If that's the case, then the old deck really just needs the +12v battery and GND hooked up to it. Forget splicing the entire harness together... if that's the case.
 

Bobo_686

Shiny things amuse me
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i donno, i just have 3 wires piggybacked...the red, black, and yellow, and the rest of the harness is capped ; ive got my old HU stuffed back in the dash tho, heh, doesnt look that good if u put my cupholder down :-D

if you want some pics, PM me soon, i plan on takin my dash apart soon an ill sho u some pics
 




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