How To: Wiring secondary o2 sensor directly to ecu
#1
Honda-Tech Member
Thread Starter
Join Date: Aug 2006
Location: 760
Posts: 524
Likes: 0
Received 0 Likes
on
0 Posts
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.....
#2
Honda-Tech Member
Join Date: Aug 2008
Location: Eugene, OR
Posts: 346
Likes: 0
Received 0 Likes
on
0 Posts
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.....
Worked. Thanks!
#3
Honda-Tech Member
Thread Starter
Join Date: Aug 2006
Location: 760
Posts: 524
Likes: 0
Received 0 Likes
on
0 Posts
Re: How To: Wiring secondary o2 sensor directly to ecu
np.... figured that it would help somebody, considering i beat my head against the wall trying to figure it out
#4
Honda-Tech Member
Join Date: Aug 2008
Location: Eugene, OR
Posts: 346
Likes: 0
Received 0 Likes
on
0 Posts
Re: How To: Wiring secondary o2 sensor directly to ecu
It worked for a day then my cel came back on
but I reset it again, so far it has worked for 1 full day again lol
but I reset it again, so far it has worked for 1 full day again lol
#7
Honda-Tech Member
Thread Starter
Join Date: Aug 2006
Location: 760
Posts: 524
Likes: 0
Received 0 Likes
on
0 Posts
Re: How To: Wiring secondary o2 sensor directly to ecu
maybe becasue it's missing 1 wire???...lol just a thought...
next time read the thread before posting ignorant bs, thanks.
TTT for somebody with some actual insight
Trending Topics
#8
Honda-Tech Member
Join Date: Aug 2008
Location: Eugene, OR
Posts: 346
Likes: 0
Received 0 Likes
on
0 Posts
Re: How To: Wiring secondary o2 sensor directly to ecu
I keep resetting it and then it comes back within 1 or 2 days. Lame!
When I have time I will check wiring again...
When I have time I will check wiring again...
#9
Junior Member
Join Date: Jul 2007
Location: Oceanside, CA, USA
Posts: 145
Likes: 0
Received 0 Likes
on
0 Posts
Re: How To: Wiring secondary o2 sensor directly to ecu
man i cant tell you how long ive been looking for this answer!!! thank you and im gona dive in and see if i can fix mine also. ill post and let you know how it goes. THANK YOU!!
#16
Honda-Tech Member
Join Date: Mar 2007
Location: branford, ct, usa
Posts: 830
Likes: 0
Received 0 Likes
on
0 Posts
Re: How To: Wiring secondary o2 sensor directly to ecu
Hey I am having this problem 65-secondary o2 sensor heater wire..
My car is a 96 dx with an EX harness just like you..
I am about to wire the sensor straight to the ecu but wondering if you guys are still having issues with the cel coming back on intermittently??
Also, how exactly did you pin the wires into the ecu connector? Do they just stick right into it?
My car is a 96 dx with an EX harness just like you..
I am about to wire the sensor straight to the ecu but wondering if you guys are still having issues with the cel coming back on intermittently??
Also, how exactly did you pin the wires into the ecu connector? Do they just stick right into it?
#17
Honda-Tech Member
Join Date: Aug 2008
Location: Murfreesboro, TN, US
Posts: 109
Likes: 0
Received 0 Likes
on
0 Posts
#19
Re: How To: Wiring secondary o2 sensor directly to ecu
Can anyone verify the obd2b info DeucesWild posted? white=a23, green=c18, black=a8? Just put a b16a2 in my 99 hatch and this is the only thing I'm unsure of
#20
Honda-Tech Member
iTrader: (2)
Join Date: Dec 2007
Location: Bay Area, CA
Posts: 4,083
Likes: 0
Received 0 Likes
on
0 Posts
Re: How To: Wiring secondary o2 sensor directly to ecu
#24
Re: How To: Wiring secondary o2 sensor directly to ecu
I'm also having this issue with my 98 EX engine i swapped into my 99 DX car. I'm using a 99 EX engine harness so now i need to wire in the second O2 sensor. I had just finished extending the wires and was going to install them into the ECU connectors, when i noticed there are already wires in the same location in the ecu connector where i'm supposed to wire the sensor into. So im wondering if i have to remove the wires already in it, but im not sure if it will cause any problems. Or should i just splice into them, but again i dont know if it will cause any problems.
#25
Honda-Tech Member
Join Date: May 2009
Location: Raleigh, NC
Posts: 114
Likes: 0
Received 0 Likes
on
0 Posts
Re: How To: Wiring secondary o2 sensor directly to ecu
Has there been a clearcut fix for this issue?
I am using OBD2a..
I also need to wire up my rear 02 sensor..
I clicked on the link sir ash posted and I got a virus warning..
I am using OBD2a..
I also need to wire up my rear 02 sensor..
I clicked on the link sir ash posted and I got a virus warning..