JDM installation mods with pics - Honda Prelude Forum

red92s · 12-15-2002, 09:22 AM

Here are some of the basic wiring and equipment modifications needed for the installation of my "S" model harness onto the JDM H22a. I know this has been gone over a few times, but never with pics. I'll do a more comprehensive writeup at a later date.

Test fitting US harness to JDM engine. Notice everything is labeled for easy connection.

The JDM engines lack and engine coolant temp. sensor that the US engines have. It is located on the upper radiator neck. I just swapped the neck from my F22 (with sensor) onto the JDM engine. The ECT plug on the US harness now has a mathing sensor on the engine.

Oxygen Sensor: The O2 sensor on the F22 is mounted in front of the engine, right by the radiator. On H22's and H23's, its mounted behind the engine, on the downpipe. The F22 wiring for the O2 sensor will not reach the new location (and also has a different connector). I removed the JDM plug from its harness, with about 6" of wiring attached. This was used to lenthen the senor wires on the US harness to the appropiate location (plug temporarily taped in place).

The SECOND ECT plug (NOT the one mentioned earlier) was removed from its wire loom to allow the distributer plugs to get closer to the distributer (green plug, left side of frame). This may not have been entirely necessary, in retrospect.

The oil pressure sensor plug on the US harness has a push-on terminal (the JDM plug is a ring terminal), and is not long enough to reach the JDM oil pressure sensor. I just cut the JDM plug off with a few inches of wiring, and spliced it onto the US harness, extending the wires and adding the ring terminal all at once.

VTEC wiring mods coming shortly. . .

red92s · 12-15-2002, 09:27 AM

CONTINUED. . .

I used the plastic harness cover that goes over the JDM H22 valve cover. No functional reason, I just thought it looked more purdy like this. it just snaps off the JDM harness once you cut the tape, reinstalled the same way.

The US fuel rail was used with the JDM injectors. Here, you can see the US rail and US injector wiring.

Scalifludesi · 12-15-2002, 11:18 AM

Good stuff. Keep those pics comin'

[SUB[EX] · 12-15-2002, 04:42 PM

yea good pics, i didnt have time to do pics on my install's. I was in a rush to finish in record time.
Dont forget to run the vtec wires to the ecu and not just to the harness. haha I ran my new wires from the sensors to the harness, then forgot to run them from the harness to the ecu. Stupid huh?