Ex 02 Sensor Wiring Harness
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Ex 02 Sensor Wiring Harness
Ok It's Me again I installed that engine and wiring harness but theres a slight problem with the 02 sensors on the EX wiring harness theres only a plug for one does anybody no what i'm talking about. I guess I need one of you EX guys to help me out and tell me where the other one is
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Re: Ex 02 Sensor Wiring Harness
there are two o2 sensors. one right before the cat (on the header) and one ON the cat.....
both plug into a 4pin connector.
for an EX anyways
both plug into a 4pin connector.
for an EX anyways
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Re: Ex 02 Sensor Wiring Harness
Negative. The EX wiring harness only has the primary o2 sensor wired into it.
The secondary is in a different harness that comes from the underdash fusebox.
It can be hardwired from the ecu if you know what you're doing. I've done it before but its been a good while.
Remember that its the PRE-CAT sensor that's contained in the EX wiring harness, that's the primary sensor. The clip that's on the ex harness does not fit into the primary dx/lx sensor, so it will seem like it should plug up into the secondary. IT DOES NOT, DO NOT PLUG THE SECONDARY SENSOR INTO THE WIRING HARNESS unless you want your car to run like ***.
Just cut the clip for the primary sensor off of the old harness and wire it in place of the existing o2 clip on the ex harness and do some research to figure out how you need to go about wiring in the secondary. Its pretty straightforward, all of the resources you need are here on this site.
Keep in mind this is only applicable for 01-02. Starting in 03, maybe 04, Honda started integrating true wideband sensors in place of the crummy narrowbands. In that case, its best to wire into a relay for the wideband. But there are alot of variables. Depends on the ECU and the harness. But if you're using an ECU that uses a primary wideband, you have to use the stock wideband.
The secondary is in a different harness that comes from the underdash fusebox.
It can be hardwired from the ecu if you know what you're doing. I've done it before but its been a good while.
Remember that its the PRE-CAT sensor that's contained in the EX wiring harness, that's the primary sensor. The clip that's on the ex harness does not fit into the primary dx/lx sensor, so it will seem like it should plug up into the secondary. IT DOES NOT, DO NOT PLUG THE SECONDARY SENSOR INTO THE WIRING HARNESS unless you want your car to run like ***.
Just cut the clip for the primary sensor off of the old harness and wire it in place of the existing o2 clip on the ex harness and do some research to figure out how you need to go about wiring in the secondary. Its pretty straightforward, all of the resources you need are here on this site.
Keep in mind this is only applicable for 01-02. Starting in 03, maybe 04, Honda started integrating true wideband sensors in place of the crummy narrowbands. In that case, its best to wire into a relay for the wideband. But there are alot of variables. Depends on the ECU and the harness. But if you're using an ECU that uses a primary wideband, you have to use the stock wideband.
Last edited by andyman97; Feb 20, 2008 at 11:00 AM.
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