Wiring Secondary O2 Sensor to ECU
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Wiring Secondary O2 Sensor to ECU
This has been hit on quite a bit but I haven't read anything that tells me exactly how to hook up my secondary O2 sensor.
Background:
Daughter had 03 Civic LX (D17A1) and blew the motor because she forgot to check the oil, ever. I bought another one at a salvage yard and had it installed. Dealt with a CEL for quite some time and then a mystery oil leak. The CEL was because of a missing EGR Valve that has now been replaced and the mysterious oil leak was coming from the V-TEC. That has now been fixed.
New Issue:
I have the D17A2 motor, the EX ECU, and the EX Engine wiring harness in my 2003 Civic LX. All is hooked up with the exception of the O2 Sensors. When I was attempting to hook them up, I discovered that there is only one connector on the harness and of course I have a primary and a secondary O2 sensor. The secondary matches up just fine but the primary does not. I will switch the connectors on the O2 sensors and hook up the primary. I believe that will take care of that. As far as the secondary O2 sensor goes, I have no idea other than what I've read.
Please help:
Secondary O2 Sensor: One Black wire; One Grey wire: and 2 white wires.
This is what I'm tracking as the correct diagram for the ECU as it pertains to the O2 sensors.
On the ECU Connector A pin 14: blk/wht - Secondary O2 Sensor heater control
On the ECU Connector A pin 25: wht/red - Secondary O2 Sensor
On the ECU Connector E pin 2: wht/red - Secondary O2 Sensor EX Only
On the ECU Connector E pin 6: blk/wht - Secondary O2 Sensor heater control EX only.
I think the ECU Wiring is correct but it just doesn't make any sense to me. If I could have some tell me where to plug my black, grey and two white wires, I will get this dude up and running in the morning.
In advance, I appreciate your help here and apologize for asking the same question in a different manner.
Background:
Daughter had 03 Civic LX (D17A1) and blew the motor because she forgot to check the oil, ever. I bought another one at a salvage yard and had it installed. Dealt with a CEL for quite some time and then a mystery oil leak. The CEL was because of a missing EGR Valve that has now been replaced and the mysterious oil leak was coming from the V-TEC. That has now been fixed.
New Issue:
I have the D17A2 motor, the EX ECU, and the EX Engine wiring harness in my 2003 Civic LX. All is hooked up with the exception of the O2 Sensors. When I was attempting to hook them up, I discovered that there is only one connector on the harness and of course I have a primary and a secondary O2 sensor. The secondary matches up just fine but the primary does not. I will switch the connectors on the O2 sensors and hook up the primary. I believe that will take care of that. As far as the secondary O2 sensor goes, I have no idea other than what I've read.
Please help:
Secondary O2 Sensor: One Black wire; One Grey wire: and 2 white wires.
This is what I'm tracking as the correct diagram for the ECU as it pertains to the O2 sensors.
On the ECU Connector A pin 14: blk/wht - Secondary O2 Sensor heater control
On the ECU Connector A pin 25: wht/red - Secondary O2 Sensor
On the ECU Connector E pin 2: wht/red - Secondary O2 Sensor EX Only
On the ECU Connector E pin 6: blk/wht - Secondary O2 Sensor heater control EX only.
I think the ECU Wiring is correct but it just doesn't make any sense to me. If I could have some tell me where to plug my black, grey and two white wires, I will get this dude up and running in the morning.
In advance, I appreciate your help here and apologize for asking the same question in a different manner.
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Registered!!
Joined: Nov 2005
Posts: 37
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Rep Power: 0 Re: Wiring Secondary O2 Sensor to ECU
This has been hit on quite a bit but I haven't read anything that tells me exactly how to hook up my secondary O2 sensor.
Background:
Daughter had 03 Civic LX (D17A1) and blew the motor because she forgot to check the oil, ever. I bought another one at a salvage yard and had it installed. Dealt with a CEL for quite some time and then a mystery oil leak. The CEL was because of a missing EGR Valve that has now been replaced and the mysterious oil leak was coming from the V-TEC. That has now been fixed.
New Issue:
I have the D17A2 motor, the EX ECU, and the EX Engine wiring harness in my 2003 Civic LX. All is hooked up with the exception of the O2 Sensors. When I was attempting to hook them up, I discovered that there is only one connector on the harness and of course I have a primary and a secondary O2 sensor. The secondary matches up just fine but the primary does not. I will switch the connectors on the O2 sensors and hook up the primary. I believe that will take care of that. As far as the secondary O2 sensor goes, I have no idea other than what I've read.
Please help:
Secondary O2 Sensor: One Black wire; One Grey wire: and 2 white wires.
This is what I'm tracking as the correct diagram for the ECU as it pertains to the O2 sensors.
On the ECU Connector A pin 14: blk/wht - Secondary O2 Sensor heater control
On the ECU Connector A pin 25: wht/red - Secondary O2 Sensor
On the ECU Connector E pin 2: wht/red - Secondary O2 Sensor EX Only
On the ECU Connector E pin 6: blk/wht - Secondary O2 Sensor heater control EX only.
I think the ECU Wiring is correct but it just doesn't make any sense to me. If I could have some tell me where to plug my black, grey and two white wires, I will get this dude up and running in the morning.
In advance, I appreciate your help here and apologize for asking the same question in a different manner.
Background:
Daughter had 03 Civic LX (D17A1) and blew the motor because she forgot to check the oil, ever. I bought another one at a salvage yard and had it installed. Dealt with a CEL for quite some time and then a mystery oil leak. The CEL was because of a missing EGR Valve that has now been replaced and the mysterious oil leak was coming from the V-TEC. That has now been fixed.
New Issue:
I have the D17A2 motor, the EX ECU, and the EX Engine wiring harness in my 2003 Civic LX. All is hooked up with the exception of the O2 Sensors. When I was attempting to hook them up, I discovered that there is only one connector on the harness and of course I have a primary and a secondary O2 sensor. The secondary matches up just fine but the primary does not. I will switch the connectors on the O2 sensors and hook up the primary. I believe that will take care of that. As far as the secondary O2 sensor goes, I have no idea other than what I've read.
Please help:
Secondary O2 Sensor: One Black wire; One Grey wire: and 2 white wires.
This is what I'm tracking as the correct diagram for the ECU as it pertains to the O2 sensors.
On the ECU Connector A pin 14: blk/wht - Secondary O2 Sensor heater control
On the ECU Connector A pin 25: wht/red - Secondary O2 Sensor
On the ECU Connector E pin 2: wht/red - Secondary O2 Sensor EX Only
On the ECU Connector E pin 6: blk/wht - Secondary O2 Sensor heater control EX only.
I think the ECU Wiring is correct but it just doesn't make any sense to me. If I could have some tell me where to plug my black, grey and two white wires, I will get this dude up and running in the morning.
In advance, I appreciate your help here and apologize for asking the same question in a different manner.
So what the guys above don't understand is that we are missing one plug completely and that is the secondary o2 sensor, and like you i've notice on the o2 sensor there's only but it doesn't explain why the ecu has two of each (signal and sensor)
anyways if you could help me out i would appreciate it.
email me
sao33@hotmail.com
Thanks
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