Good write up Jasonst.
I wanted to add a kill switch in my 91 CRX HF. But I didn't want to kill the ECU. Only
the injectors. So I had to do some digging and with a lot of help from a friend (WeatherSpotter), I finished the install last night. Here's my "How To".
The supplies I
1, 5 pin Bosch like relay
1 momentary switch (normally open)
1 fork, or preferably ring connector
6 female insulated spade connectors
2 male insulated spade connectors
14 & 18 gauge wires
an electrical crimping/stripping/cutting tool
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First off, here's the page in my 91 CRX electrical manual for the injectors.
And here is a wiring diagram I made to show what I did. (let me know if I can improve it.)
Here, I have taken the injector resistor box out from its spot and exposed the wiring harness more.
You cut which ever side of the injector power wire you want. I did the red side, as I thought everything would tuck in better after things were put away. And I can disconnect the resistor box and replace it with a stock one later. No harm done to the main wiring harness.
(Also, use one female connector on one side of the injector power wire, and one male connector on the other, in case you want to bypass your switch.
Next, add a power lead to your relay (Pin 86). I used an already fused ignition wire. The ignition wire that is hot in the Run or Start position already had a quick connect splice in it, so I used that spot. I also soldered the power wire in. (I will be revisiting that connection to wrap it up better.)
If you would like to connect directly to the battery, you will need to add an in-line fuse to that wire, with a 15A fuse in it.
Next, add your momentary, or rocker switch. Ideas for what to use and/or where to put it can be found here: Kill Switch (EOC): Where did you install your activator? And what did you use?
I chose to use a momentary switch, and I attached it to my shifter nob. Because the switch doesn't carry much current, I used 18 gauge wire for this (14 gauge for everything else). One pin on the switch gets grounded, and the other goes to the relay (Pin 85). I soldered the wires to the switch, and used small bits of heat shrink tubing on each post.
Remove your shifter nob, and the lower dash piece. It's held in by 6 screws.
Keep the wires semi long as your shifter is a moving component!
Close up of the ground location. Better to use a ring end, appose to a fork, but I don't have any rings of the right size, right now.
It's a good opportunity to clean this area up!!
I left a small section of the wires uncovered. when I got the shifter arm back through the leather boot, it's too tight of a fit! Especially with the shifter nob on too.
Next you can attach your switch any way you like. I chose to use just electrical tape, as it allowed me to get the precise location that I wanted, and a temporary situation that I could adjust in time.
Close enough to reach easily, but not so close that I'll be bumping it.
Now it's time to wire up the relay. I chose to put it near where the hood latch release usually is. (I've relocated mine.)
The picture pretty much says it all.
Pin 87 stays open.
Loom up your wires. (I didn't loom everything.)
Put your injector resistor box back in place.
I left a length of loose wires on that end, in case I wanted to pull the box out again. I'll probably shorten the wires later.
And attach your relay to wherever suits you.
And test it out!
Mine works great! Only drawback is that it lights up the CEL. You can turn the key off, and back on, and the CEL will be gone. But as long as the key stays in the Run position, and you use the kill switch just once, you'll have a CEL, at least with an 88-91 CRX.
I hope this write-up helps some of you! And another HUGE
thanks to WeatherSpotter for helping me with the wiring!!!