DOHC_EF

I have a 1991 hf wiring harness that I am planning to use for my dohc zc engine swap. My car is a 1991 CRX dx. I have notice the wiring harness off the hf has on extra plug that I don't know what it is. Its near the fuze box if it helps. I've searched and I have gotten nothing. Thanx

88DXCRX

The easy way to do it is use the DX harness.
Use the plugs from the ZC engine you get or the from HF harness
to alter the DX one ..
I know of a write-up the guy used an Si harness but its not very fun and alot
more involved..

written by CRX resource member "cui" {Not sure if it is correct}
I spent the whole day trying to figure out how to make the Si harness to work...and I almost gave up...but I was too stubborn to say no


Here's what need to get the Si harness to work...in fact, I think it is much better than modifying the DX...(that is, once you figured out which wire goes to which...)

1) Parts you need:

1a) you need to add 4 wires totoal thru the firewall. (try to get them the same color, it will make your life much easier.)

* 1 wire for Cylinder Position Sensor 1, ECU pin# C1, Blue/Green, 4 ft
* 1 wire for Cylinder Position Sensor 2, ECU pin# C2, Blue/White, 4ft
* 1 wire for Injector #2, Red, ECU pin# A3, 6 ft
* 1 wire for Injector #4, Yellow, ECU pin# A7, 6ft

1b) * you will also need a DX 14 pin female connector for the right hand connector, C175...as the DX has 14 pin, but the Si harness only has 8 pin.

1c) * you also need to source a 6 pin square male connector, C212. This connector is missing from the DX.

1d) * couple pins for ECU...source for junk yard.

2. Wire connection
2a) on the round connector right next to the main fuse panel, C210, find the TW sensor wire, the Red/White wire, and cut.
Solder the connector end wire to the extended Blue/Green wire...you just connected the Cylinder position 1 wire.

2b) the remaining loose end of Red/White wire,
connect to the Red/White wire of C212, the 6 pin connector right next to the C210. This the Si TW sensor wire.

2c) find the Red/Yellow wire on C210, the the TA sensor, cut. (same as in procedure 2a)
Connect the connector end wire to the extended Blue/White wire, this is for the Cylinder sensor C2.

2d) connected the loose end of Red/Yellow to the 6 pin C212 Red/Yellow wire. This is the Si TA sensor.


Now...here's the hard part...
2e) on the left hand side, remove the all the wires on the 8-pin connector of C175...plug them in the the 14 pin DX female connector describe in 1b...

here's the order:
Si C175:
pin1, Red, #2 Injector
pin2, Brown, #1 Injector
pin3, Lt Blue, #3 Injector
pin4, Yellow, #4 Injector
pin5, Black/Yellow
pin6, Blue
pin7, Blue/Yellow
pin8, Yellow/black...resistor box

Plug Si pin#2, Brown, to the DX pin #5, Yellow, this is for Injector #1.

Plug Si Pin#3, Lt Blue, to DX pin# 3, Red. Injector #3.

Plug Si Pin# 5, 6, 7 to respective DX colored pin.

Plug Si Pin# 8, Yellow/Black to DX pin #1, Yellow/Black...this is for the Main Relay.

Connect Si pin#1, Red, to the extended wire Red, for #2 injector

Connect Si pin#4, Yellow, to th extended wire yellow, for #4 injector.

Now, there is 4 more wires need to be routed from C175 to C212. They are color-matched.

they are Yellow/Green, Green/Balck, White, Yellow.


3) swap pins at ECU (move two wires, and add two wires)

3a) move C1, Orange, to B10, for the new Si Crank Angle pin location
3b) move C2, White, to B12
3c) add the extended Blue/White wire to C1, for Cylinder Sensor 1.
3d) add the exnteded Blue/Greeen wire to C2, for Cylinder Sensor 2.

That's it! It only took me 8 hours to figure out which wire goes to which I hope this is easier for people choose to use the Si harness in the future...

DOHC_EF

So I figure I can't use an hf wiring harness in my dx, right?