How To: Wiring secondary o2 sensor directly to ecu
02-15-2010, 06:56 PM
#26
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Re: How To: Wiring secondary o2 sensor directly to ecu
I have the same problem, but I have a B16A2 in a 92 EG CX with a P28. I used the OBD1 harness and just added vtec. How can I connect the 02 sensor?
Thanks
Thanks
06-17-2010, 11:24 AM
#28
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Re: How To: Wiring secondary o2 sensor directly to ecu
I have spent a lot of time researching this topic, and it seems as though there are a lot of people like myself looking for this information. I am not the best when it comes to wiring, so maybe that is why it was so hard for me to figure out, or maybe this is just something that everybody else just inherently knows this information. Either way, it seems to be a problem, and this is the solution.
The Problem
If you own an EK that did not come from the factory with VTEC and you decide to swap in a vtec motor, you have a couple of options when it comes to the harness. You can:
1. use your stock DX/other harness, and wire in VTEC, and do whatever other mods needed for your specific swap.
2. use an EX/SI harness, this way everything is already wired in (or so you think)
The problem if you use an EX/SI harness is that although everything is wired in, you will be missing your secondary o2 sensor. This is because in an EX/SI car, the secondary o2 sensor comes from the cabin harness that is attached to the car itself, and your DX car will not have the connection.
The Solution
If you have decided (like myself) to get the EX/SI harness thinking that there will be no wiring, you can do one of the following:
1. buy and install the cabin harness from an EX/SI with same OBD2x version as your car/engine harness/ecu.
2. Wire the secondary o2 sensor directly to your ecu. This is the route I decided to go, because i thought it would/should be easier than finding/installing the cabin harness.
The Wiring
So on your o2 sensor, you should have 4 wires and they should be:
1 green wire (this is the SENSOR ground)
1 white wire (this is the sensor signal wire)
2 black wires (these have been labeled as the "Heater wires")
All you need to do is wire THREE wires to the ECU. That's right, THREE wires, not four! Here's what you do:
This pertains to OBD2a only]
Green wire (signal wire) = D13
White wire (sensor wire) = D14
1 Black wire (heater wire) = A6
1 Black wire (heater wire) = some 12v lead. you could wire this to the battery directly (if that's what you want to do), I wired it to a 12v that got hot with the key on only. This way it couldn't pull power with the key in the OFF position. From what I understand, the two black wires create a circuit, one needs 12v the other needs a ground? -something like that- I constantly referenced this site http://technet.ff-squad.com/wiring.obd2a.htm for information.
This info should work for an OBD2b, given that you research and find the correct pin locations for your car. http://technet.ff-squad.com/index.htm has the pinout schematics for OBD2b, it should be something like:
White = A23
Green = C18???? (not sure if this is correct, somebody pls verify)
Black = A8
Black = 12v lead
Hopefully this information helps somebody.....
The Problem
If you own an EK that did not come from the factory with VTEC and you decide to swap in a vtec motor, you have a couple of options when it comes to the harness. You can:
1. use your stock DX/other harness, and wire in VTEC, and do whatever other mods needed for your specific swap.
2. use an EX/SI harness, this way everything is already wired in (or so you think)
The problem if you use an EX/SI harness is that although everything is wired in, you will be missing your secondary o2 sensor. This is because in an EX/SI car, the secondary o2 sensor comes from the cabin harness that is attached to the car itself, and your DX car will not have the connection.
The Solution
If you have decided (like myself) to get the EX/SI harness thinking that there will be no wiring, you can do one of the following:
1. buy and install the cabin harness from an EX/SI with same OBD2x version as your car/engine harness/ecu.
2. Wire the secondary o2 sensor directly to your ecu. This is the route I decided to go, because i thought it would/should be easier than finding/installing the cabin harness.
The Wiring
So on your o2 sensor, you should have 4 wires and they should be:
1 green wire (this is the SENSOR ground)
1 white wire (this is the sensor signal wire)
2 black wires (these have been labeled as the "Heater wires")
All you need to do is wire THREE wires to the ECU. That's right, THREE wires, not four! Here's what you do:
This pertains to OBD2a only]
Green wire (signal wire) = D13
White wire (sensor wire) = D14
1 Black wire (heater wire) = A6
1 Black wire (heater wire) = some 12v lead. you could wire this to the battery directly (if that's what you want to do), I wired it to a 12v that got hot with the key on only. This way it couldn't pull power with the key in the OFF position. From what I understand, the two black wires create a circuit, one needs 12v the other needs a ground? -something like that- I constantly referenced this site http://technet.ff-squad.com/wiring.obd2a.htm for information.
This info should work for an OBD2b, given that you research and find the correct pin locations for your car. http://technet.ff-squad.com/index.htm has the pinout schematics for OBD2b, it should be something like:
White = A23
Green = C18???? (not sure if this is correct, somebody pls verify)
Black = A8
Black = 12v lead
Hopefully this information helps somebody.....
03-20-2012, 10:40 AM
#30
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Re: How To: Wiring secondary o2 sensor directly to ecu
ok, i would hate to bring this old topic back however i need to. i recently bought a car that i have found out will not pass inspection and this is why. basically the only question i have is what seconday o2 sensor do i buy? i ask this becasue car year and engine are diffrent.
car-96 ek hatch
motor-b16a2
ecu-p72
primary o2 is 96 ek dx sensor so should the rear be the same? or shold it be for the 2000 civic si or b16a2 being ran by a p72? i jsut dont want to re order the wrong one! any help is appreciated guys!!!! i really want to get this car to pass nys inspection and this is the only thing holding me back!
car-96 ek hatch
motor-b16a2
ecu-p72
primary o2 is 96 ek dx sensor so should the rear be the same? or shold it be for the 2000 civic si or b16a2 being ran by a p72? i jsut dont want to re order the wrong one! any help is appreciated guys!!!! i really want to get this car to pass nys inspection and this is the only thing holding me back!
03-04-2013, 02:14 PM
#33
Honda-Tech Member
Re: How To: Wiring secondary o2 sensor directly to ecu
Hate to revive an old thread but like zildjianmatt said, do you splice the new wires with the wires already connected to the ecu? Or do you de-pin and cap the existing wires and just pin the new wires to the ecu?
I plan on doing this to my ek as well, a little bit of clarification would help.
Thanks
I plan on doing this to my ek as well, a little bit of clarification would help.
Thanks
05-17-2013, 08:36 PM
#34
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Re: How To: Wiring secondary o2 sensor directly to ecu
If the wires are there you splice or completely cut them off, no telling where they are going if you had plans of running them to the ecu. If you are good at depinning them go for it. I would highly suggest, if possible, that you depin them to make it clean.
05-26-2013, 10:08 AM
#35
Honda-Tech Member
Re: How To: Wiring secondary o2 sensor directly to ecu
ok so im trying to have all the issues figured out before pulling my motor so im putting a OBD2B JDM GSR into a 00 civic dx hatch im using the 00 si engine harness and using a OBD1 p72 ecu with a jumper how would i wire in the secondary o2 sensor in this case so i will not throw a check engine light?
10-26-2013, 10:50 AM
#36
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Re: How To: Wiring secondary o2 sensor directly to ecu
Ok. I have a problem with code 65. I have a usdm b18b engine in my 97 civic dx running a obd2a ecu. The secondary o2 sensor is brand new and has been directly wired to ecu and the cel keeps coming on as soon as the car is turned on. Does anybody have any tips?
Last edited by Jaycee52; 10-26-2013 at 11:09 AM.
11-04-2013, 05:13 AM
#38
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Re: How To: Wiring secondary o2 sensor directly to ecu
It's wired exactly how it says on one of the first posts. The THREE WIRE obd2a way. Could my ecu be bad? I can't think of anything else.
10-22-2016, 12:11 PM
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Re: How To: Wiring secondary o2 sensor directly to ecu
Anyone have a new link to this need help with this
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