ThePsuedoMonkey
XS400 Addict
As I mentioned before, the stock signal relay didn't work for me when I swapped to the smaller incandescent rear signals. In a nutshell, there were three obstacles to overcome for the LED conversion: (1) the relay, (2) the self-canceling unit, and (3) the indicator on the gauge cluster. The first relay I used didn't work, probably because it was cheap, but the one that did was a "CF14 JL-02" that I bought on ebay (link provided for the lazy ). I needed to re-tab the connector for it though.
To address the second issue, I simply disconnected the self-cancel unit. This gives you two more issues: (A) You need to run a separate ground to the flasher, in order to replace the yellow/green wire that ran to the unit, and (B) now we NEED to fix #3 for safety.
But first, some electrical engineering! The indicator leads are the individual circuits to the left/right signals. This works for incandescent bulbs because they need a certain amount of current before they light up, and the little indicator light uses up enough that the opposite circuit acts as a ground, but not enough to light 'em up. The LEDs are way more efficient, so leaving this setup makes all of the signal lights go on at the same time. To remedy this, I built my own special turn indicator light.
I scavenged the base to an SMD replacement bulb, some circuitboard, two white LEDs (FV=4.6V), a 500 ohm resistor, and some magnet wire. Take the LEDs and thread the + terminals through the board and put on ~1cm of tiny heat shrink, apply fire and squish. Solder the - terminals together with one terminal of the resistor, then the other to the magnet wire (after exposing to metal by scratching with a razor blade) and cover with ~3cm of heat shrink. This magnet wire will be the ground, but the metal inside the housing is no good, so it gets wired to where one of the reflectors would have been.
Easy peasy (at least when compared to what I thought a week ago)
To address the second issue, I simply disconnected the self-cancel unit. This gives you two more issues: (A) You need to run a separate ground to the flasher, in order to replace the yellow/green wire that ran to the unit, and (B) now we NEED to fix #3 for safety.
But first, some electrical engineering! The indicator leads are the individual circuits to the left/right signals. This works for incandescent bulbs because they need a certain amount of current before they light up, and the little indicator light uses up enough that the opposite circuit acts as a ground, but not enough to light 'em up. The LEDs are way more efficient, so leaving this setup makes all of the signal lights go on at the same time. To remedy this, I built my own special turn indicator light.
I scavenged the base to an SMD replacement bulb, some circuitboard, two white LEDs (FV=4.6V), a 500 ohm resistor, and some magnet wire. Take the LEDs and thread the + terminals through the board and put on ~1cm of tiny heat shrink, apply fire and squish. Solder the - terminals together with one terminal of the resistor, then the other to the magnet wire (after exposing to metal by scratching with a razor blade) and cover with ~3cm of heat shrink. This magnet wire will be the ground, but the metal inside the housing is no good, so it gets wired to where one of the reflectors would have been.
Easy peasy (at least when compared to what I thought a week ago)