Written By: KingDNH
First unplug the battery's negative terminal:
Then remove the strut tower brace and the mount from the passenger's side (you'll need 2 17mm wrenches/sockets for the strut bar and a 12mm wrench for the mount)
Then un-clip the harness; you can see the little holder in the picture.
There's ONLY 2 10mm bolts holding the ECU box to the car; remove the two bolts and pull the ECU out while twisting counter clock wise on the box.
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Remove all 10mm bolts from the box.
There's two plastic locks. One on each side.
This is how the ECU looks like once you open the box:
Remove the top 3 10mm bolts to remove the ECU mount from the box, then remove the other 4 10mm bolts from the mount, to remove it from the ECU:
This is how the ECU looks without the mount:
Move the lever to the position shown to remove the ECU from the wiring harness:
Pull the ECU to remove it:
This is how the pins look like on the ECU:
Picture of the harness:
Turn the lever to about 50% and pull up a little bit, and it should come off as shown:
Pop up the 4 safeties and remove the ehm.. whatever that thing is called:
Remove the glove box and panel to get access to the firewall. (inside of car)
This is where the wires are going to be coming to the inside of the car.
Insert the NEO's harness through the ECU box ventilation hole. Wires pointing to the sky and the connector to the floor.
This is the other side of the box, and you can see the ventilation hose where we'll route the NEO harness through:
The NEO Harness connectors are on the other side of the hose now; just route them to the inside of the car.
Pull lightly on the NEO harness from the inside of the car, while being careful not to pull the wires from the ECU box.
Remove the ECU harness from the rest of the box, thus it'll be a LOT easier to work with the very short wires!
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Now for the good part:
Please refer to the following pictures for the location of the wires:
2002 & 2003
NEO
2004 - 2006
Thanks to Gurov for above pictures.
Splice the POWER wire as shown:
Now connect the Solid RED NEO wire to the place shown above, then attach the Red w/white stripe wire to the same wire as above, but further away from the ECU, as shown:
Place a drop of solder on each connection and use electrical tape to secure the wires. Do this for all of the following wires as well.
Now for the NEO GROUND wires. VERY IMPORTANT: Brown NEO wire has to be closer to the ECU than the Black NEO wire, and on the same wire, as shown!!!!!
Green NEO wire to RPM wire.
Gray NEO wire to Throttle wire.
Cut the MAF Wire as shown:
Then Connect the NEO yellow wire to the MAF wire on the ECU side!
And the NEO white wire to the other side.
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WE ARE DONE!!!!
now just to wrap things up:
Tape the unused NEO wires to prevent any shorts or whatever.
Place Everything back together.
Just connect the NEO to the Harness and Enjoy.
Make sure the sensor type on the neo is on hot wire 24 in 24 out for 02-03, and 18 in 18 out for 04-06