CEL: Code 41.. Primary Oxygen Sensor Heater

onesikEJ8

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I just replaced my Primary Oxygen Sensor and when I wired it and installed it, I started the car and through a CEL. I checked it and it was the heater of the primary oxygen sensor. So what I did then was switch the two wires that could have been switched. The reason why I say that is because of the four wires, 2 of them were the same color so I assumed those two went to the original harness of the same colors.

Anyway, I switched the two wires and started my car again, and still was throwing the same code. I already checked my #15 fuse under the dash and it is fine. What are the odds of it being a faulty o2 sensor?

Thanks ahead
Kyle
 

RonJ

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Put the year Civic in your signature. Did you test fuse 15 with a test light or multimeter as described at the fuse testing link in my signature? If so, then your wiring job is the prime suspect. You must figure out in advance exactly how an aftermarket O2 sensor should be wired because there is potential to fry the ECU. Start by verifying proper wiring and then check whether the heater power wire gets battery voltage with the key in ON(II).
 


onesikEJ8

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the multimeter and test light are in my dad's work truck. i did just replace the fuse instead of testing, and i still had a cel. then i switched the two wires with the fuse still installed, and still a cel. so next thing to check to see if the heater power wire is getting battery voltage?
 

oc_civic

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the multimeter and test light are in my dad's work truck. i did just replace the fuse instead of testing, and i still had a cel. then i switched the two wires with the fuse still installed, and still a cel. so next thing to check to see if the heater power wire is getting battery voltage?
you should not be arbitrarily switching wires around IMO...

PIf so, then your wiring job is the prime suspect. You must figure out in advance exactly how an aftermarket O2 sensor should be wired because there is potential to fry the ECU.
this..

i have even seem some cases where aftermarket O2 sensors have just sucked and not worked properly in our cars.. i have PERSONALLY had one that i tried once and got a CEL.. i replaced it with an OEM one and the problem was gone.. could have been my wiring or just the O2 sensor itself.. but as pointed out verifying the proper wiring is really important since its not going to just be plug and play..
 


RonJ

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1) If you are switching wires around, you are not absolutely sure about how the sensor should be wired. You must not guess. Find the correct wiring information or call the manufacturer.

2) Did you use the correct procedures for wire splicing? Click here.

3) Use a multimeter to check the O2 sensor heater wires for an open or short.
 

onesikEJ8

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youre definitely right oc .. plus i just read that soldering those wires will lead to early failure of the o2 sensor. I did not know this, I figured I was doing it right by soldering them, so chances are, I have a dead sensor.
 

moebiius

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1992 civic cx hatchback with p05 ecu/ECM, threw a cell, code 41, I replaced the primary oxygen sensor heater above the exhaust manifold with a single wire o2 sensor made by denso. My problem is it still throws that code. There's only one wire and I lost the crimping piece so I soldered it. I heated the wire that didn't have the sensor on it and then added the sensor wire quickly, did I somehow Jack my sensor? Is there a way to test single wire sensors? Thanks
 

Jersey8

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NGK, oem plug ftw. its def worth the extra money
 

moebiius

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RonJ. Anything on my issue? Still driving just fine, just check engine light still on
 

Ej8civic96

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hi i have a problem on my 96 honda civic ex the check engine light is on and it gives me the front o2 heater sensor code idk if it has any thing to do with the after market dc headers and a megan hi flow cat with a buddyclub exhaust with the pipes nothing is stock and i have a cold air intake so i bought i new front heater sensor and put it in and still gives me the code even after i take out the batt off as soon as i plug the batt in and start the car 6 sec the light comes back on and i have and emmsion test this month i had put back my regular exhaust manifold and still the same crap im going to buy a stock oem air intake and see if thats it but idk if thats helps i remember my friend telling me when he pluged the computer under the dash it said it air intake flow was hi he tried dealting the code and it came back i took it to advance auto parts and they delated it and still came back so now im stuck any advice to who had the same problem and had it fix ?? please help i read back in the thred but it doesnt seem to help
 


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