hi,

i have a 96 dx civic hatchback swap a 00 civic si engine and use a 96-98 ex harness does not have the second o2 sensor wire. I'm trying to wire the second o2 sensor to my car. I know the 4 wire go to the 02 senor but i don't where the other end of the wire go to the car. so far I figure out the three wire that connect to the ECU but i don't 'know where the last wired go to? anybody done a 96-98 dx swap should know what i'm talking about. give me some help thanks..

 

I think the 4th wire is power, it should tee into the power wire for the first sensor. The power wire is the only wire on the first sensor that doesn't go to the ECU. These power up the sensor heaters through the infamous fuse #15 circuit.

 

i was wonder where is the best way to connect power to the o2 sensor in my car? cause i don't want to have a short circuit.

 

Follow the Blk/Yel wire of the primary O2 sensor along the wire harness. It will lead you to the blue 14P C115 connector that merges all Blk/Yel wires from many components to fuse 15. One of the Blk/Yel wires at this connector is for the secondary O2 sensor.

 

thanks a lot mk378 and RonJ for helping me out..

 

helpful diagram

 

i'am not sure which pin is the o2 sensor...give me some advise thanks

 

Look at the rear of the connector to verify. (EDIT) Based on the diagram, you are correct. The primary and secondary O2 sensor wires are two of those terminals, though the diagram doesn't indicate which ones.

 

All of the black and yellow wires are connected together. Just pick whichever one is easiest.

 

thanks for the help, so far i back track all the wire. There are 6 wire that are black/yellow.

1. one wire go to the alternator
2. one go to the canister
3. fuel injection
4. iacv
5. one go back to the dash (don't know where it hook up to)
6. first o2 senor

before i hook the second o2 sensor to the wire (black/yellow) that go back to the dash and it work. When i drove my car it create a short circuit and blow the fuse.. Is there a way for me to connect two wire to one power source that will not make a short circuit?