Need help wiring secondary 02 in obd2b car

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I have read 20+ pages of threads here and cannot come up with an answer.

I just swapped a 99 b16a2 into a 99 civic dx. I used the b16a2 engine harness and stock B16a2 ecu. All I have left to do is wire up the secondary o2 sensor to the ecu since the wiring for that sensor is in the dash harness of a si. I'm still using the DX dash harness.

The o2 sensor I have is wired like this:

BLK WHT

BLK GRN

Can anyone tell me where each wire is supposed to go ino the ECU? I saw a few diagrams but I understand what wires go where.

From what I have read (correct me if I'm wrong), the WHT (SO2S) goes to A8, GRN (SHO2SG) goes to A23. I can not find where the BLK wires go.

Help please!
 
Originally posted by dwnthehatch@Mar 30 2005, 03:32 AM
I have read 20+ pages of threads here and cannot come up with an answer.

I just swapped a 99 b16a2 into a 99 civic dx. I used the b16a2 engine harness and stock B16a2 ecu. All I have left to do is wire up the secondary o2 sensor to the ecu since the wiring for that sensor is in the dash harness of a si. I'm still using the DX dash harness.

The o2 sensor I have is wired like this:

BLK WHT

BLK GRN

Can anyone tell me where each wire is supposed to go ino the ECU? I saw a few diagrams but I understand what wires go where.

From what I have read (correct me if I'm wrong), the WHT (SO2S) goes to A8, GRN (SHO2SG) goes to A23. I can not find where the BLK wires go.

Help please!
[post=480500]Quoted post[/post]​


IIRC obd2 only uses one O2 sensor. It's only obd0 that uses two. OBD1 and 2 use only the single 4 wire O2 sensor.
 
Originally posted by clanny@Mar 30 2005, 09:04 AM

[post=480500]Quoted post[/post]​

IIRC obd2 only uses one O2 sensor. It's only obd0 that uses two. OBD1 and 2 use only the single 4 wire O2 sensor.
[post=480596]Quoted post[/post]​



You are mistaken. The 99 B16A2 is OBD2B and used two o2 sensors. Thanks for the bump.
 
I'm not real familiar with the OBD IIb, but I would say that the two blacks, one is a ground, and the other is the 12v switched. If they don't have a place on the ECU, than they problably run into a group that ends in the harness.
 
Originally posted by dwnthehatch@Mar 29 2005, 09:32 PM
From what I have read (correct me if I'm wrong), the WHT (SO2S) goes to A8, GRN (SHO2SG) goes to A23. I can not find where the BLK wires go.
Help please!
[post=480500]Quoted post[/post]​

hope this helps but the two black wires are grounds for each sensor. also on your wiring harness (the dx harness) the o2 sensor plugs are on the engine harness but on the si harness is on the sub harness is where the o2 sensor goes. so i hope that helps you out i also am working on an obd2 set up!
 
Originally posted by civiclxb16+Mar 30 2005, 01:23 PM-->
dwnthehatch
@Mar 29 2005, 09:32 PM
From what I have read (correct me if I'm wrong), the WHT (SO2S) goes to A8, GRN (SHO2SG) goes to A23. I can not find where the BLK wires go.
Help please!
[post=480500]Quoted post[/post]​

hope this helps but the two black wires are grounds for each sensor. also on your wiring harness (the dx harness) the o2 sensor plugs are on the engine harness but on the si harness is on the sub harness is where the o2 sensor goes. so i hope that helps you out i also am working on an obd2 set up!
[post=480615]Quoted post[/post]​



So I just need to ground the black wires to the chassis?
 
yeah all i did when i did my boys swap we just put it on the therm housing and it works fine since then
 
No, not both of them. if you ground them both out, you will burn out the heater circuit.
 
Here's what I have found out:

O2%20sensor%20color%20functions.JPG


wiring.99-01.jpg


Wht - A23
Grn - C18
Blk (O2 heater control) - A8
Blk (O2 heater supply) - use a switched +12v. Factory has got this off of connector C115 which also supplies power to the EVAP purge solenoid (among other things).

I'll try it tonight.
 
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