O2 sensor codes

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robs559

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May 20, 2019
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Location
Fresno, CA
I THINK THIS IS MY SECOND POST AND I HAVE BEEN LOOKING AROUND QUITE ABIT ABOUT THIS ON THIS FORUM AND OTHERS.

I have 2005 Rubicon 2 door inline 6 100k miles had her since 2018 automatic 42rle been getting CA emissions 4 o2 sensors :

Current Issue
p0031 p0037 p0051 and p0057 . I had these beginning in November its Jan been troubleshooting since then. 02 heater circuit low

Background
Only electrical mods I put in are a tranny gauge that I splicedin near the cigarette lighter I dont think should matter. However that was in Julyish of last year so its relatively recent.

Heater Blower Motor Resistor went out and I replaced with a non mopar part from autozone. Didnt think this should cause an electrical issue and I had these codes before that occasionally.

I had a trailer hitch light connector wire in between the fuel tank skid and the frame rub a wire and it seemed to blow the tail light fuse to so I used a butt connector and zip tied it up. That was around the time this started happening though and when i originally replaced the lights went out immediately and came back.

I have also received p0431 and each time I tighten up the pipes to the exhaust manifold at the flanges and it goes away. Unsure if this is related.
Had also received the p0700 and p0720 only viewable with obd reader not on the dash and replaced the OSS with mopar part and this was resolved! Typical at my milage and age I think.
2 years ago the fusible link burnt up when the polarity was reversed on a jump start in the dark. The fusible link has been replaced. Not sure if that fried something else in the wiring harness.

I am an electrical newcomer . I bought a mulitmeter and some aligator clip wires at harborfrieght and I stayed at a holiday inn last night.

Steps Taken to Troubleshoot So Far
So far I have done these tests https://www.obd2-code.com/2017/06/p0051-o2-sensor-2-1-heater-circuit-low-jeep-chrysler.html they all check out except I have gotten some resistance values at .5ohms not under .5ohms I think those are ok. There was no short to ground while sitting still (Inifinte resistance or open circuit i believe its called) Also did this while trying to move every wire i could no beeps made though on the multimeter). Original o2s were around 4.3 ohms which seems good but I replaced anyways as Im at 100k and had to replace one just rule them out. No high resistance in the positive to the pcm connector c2 and c3 as the wiring diagram indicates .5 ohms. Or in the ground wire .4ohms.

I cleaned off the ground points ( didnt change ground strap). That helped for a while but the codes came back 100s miles.
I have replaced the 02 sensors ( i knew that probably wasnt all 4 at same time but it was at 100k miles so I did it anyways). I had replaced one o2 some time back and the other 3 were original just replaced the other 3 codes pop up still.
I checked the ASD relay first time but it had resistance of 70 ohms and switched over when jumped and Im not sure its even in the circuit as its not in the CA version of the wiring diagrams.

What's Next
I think what remains that it could be is either
A. intermittent short to ground while moving ? Problems in the wiring harness I cant detect while still yet?
B. PCM @Wranglerfix or ares? any others I should consider

Any other things I am missing that it could be ?
If its A or B should i go to my local offroad extreme for 125$ an hour to see if they can find the short or try and replace the PCM from somewhere like wranglerfix.com or someone else. Would love to gain from other experience here and skip one or the other fees if I could?

Been reading alot about this on different threads with very few actual resolutions. Seems like the federal 02 heater circuit has a fuse and the asd relay in the wiring diagram but the CA wiring diagrams dont have any mention of a fuse or a relay or Power Distribution Center in them? Makes me think that maybe PCM is hosed because it doesnt have that fuse in the circuit to protect in case of a short.

Thank you in advance for any assistance.

Rob aka hoesindifferentobdcodes
 
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I recently had this code for 1 of our O2 sensors. I simply purchased a replacement O2 sensor and swapped it in. It took about 20 minutes. The code cleared immediately after the new sensor was installed.

What brand are the new sensors?
 
Thank you Dan,
The all four is what is pointing me to pcm or intermittent short.

But replaced them with these just to rule it out. I pulled the sensors from here https://wranglertjforum.com/threads/the-official-jeep-wrangler-tj-oxygen-o2-sensor-thread.4068/ they are the ngk/ntk
2005-2006
NGK #23018 - Bank 1, Sensor 1 (Upstream)
NGK #23160 - Bank 2, Sensor 1 (Upstream)
NGK #23159 - Bank 1, Sensor 2 (Downstream)
NGK #23158 - Bank 2, Sensor 2 (Downstream)
I only drove for 3 miles after install and the codes came back on.
 
Those are definitely the right sensors in that other thread. That's also where I got my part #, BTW.
I see your point about a 'common denominator' (PCM, harness, etc.) being the root cause instead of (4) failed sensors.
I would clear the code, reset the memory, etc. and disconnect the battery long enough that you have to reenter your radio presets; then drive it again.
If they come back on, I would probably just take it to a shop that has better diagnostic tools than just the CEL & code in the dash.

BTW, does the engine struggle/lope when idling? Ours idled rough when the sensor was failing.
 
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Dan, No rough idling that I can tell although my mpgs has gone down cause I think Im always in open loop with the o2 codes and never getting to closed loop with 02 determining the gas mileage.
Thank you LJ!
 
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And the award for most unnecessary thread title of the week goes to:

"02 SENSOR HEATER CIRCUIT LOW CODES? BAD PCM? INTERMITTENT SHORT? P0031 P0037 P0051 P0057 2005 RUBICON AUTOMATIC 42rle 100K CA EMISSIONS 4 02 SENSORS"

🤦‍♂️
 
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robs559 said:
Thank you Dan,
The all four is what is pointing me to pcm or intermittent short.

But replaced them with these just to rule it out. I pulled the sensors from here https://wranglertjforum.com/threads/the-official-jeep-wrangler-tj-oxygen-o2-sensor-thread.4068/ they are the ngk/ntk
2005-2006
NGK #23018 - Bank 1, Sensor 1 (Upstream)
NGK #23160 - Bank 2, Sensor 1 (Upstream)
NGK #23159 - Bank 1, Sensor 2 (Downstream)
NGK #23158 - Bank 2, Sensor 2 (Downstream)
I only drove for 3 miles after install and the codes came back on.
Click to expand...
Did you find a solution for this CELs? I have the same issue 0031.0037.0051.0057 changed my exhaust to the flowmeter along the 4 O2 sensors (NTK) but these codes are still there, tried erasing them with an OBD but they come right away once i turn the key (no engine start) - checked the ground G105 if I recall correctly near the oil filter and it looks fine. Very frustrating issue too much money spent for nothing - in case you found a solution please share it here
 
I had the same issue with my 05. I got a PCM from wranglerfix and it fixed 3 of the 4 O2 codes. Prior to the PCM I replaced all 4 O2 sensors with NGK and replaced both front cats.
P0057 is the only one left and i've gone through 3 PCM with @Wranglerfix

I'm gonna have an electrician come out and take a look at it because I got my smog requirement for my TJ this year in commiefornia. Only thing I can think of is some wiring is messed up somewhere.

If it doesn't work I'm going to be moving my TJs residence somewhere in Ca that doesn't require smog.
 
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https://www.rubiconownersforum.com/...sions-4-o2-sensors.117309/page-2#post-1376431 has more info on my tale of woe. Dont know if its bad form posting another forum delete if it is. Just trying to get it sorted and share info.

Wranglerfix pcm seems to have caused those codes (31,37,51 ,57) to be resolved. Jeep runs better now getting actual error. New pcm got a p0431 and thats likely because my cat conv is gone.

All my research is pcm is a weak link here in the 05 06.

The downstream o2 sensors look more beat up than pam andersons diaphragm. Are you in california? Did you like that company for cats.

After changing my shorts looking at 3k carb compliant magna flow . Looking for a reasonably priced option for pipes / cats in CA
 
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lulzpwndyah said:
I had the same issue with my 05. I got a PCM from wranglerfix and it fixed 3 of the 4 O2 codes. Prior to the PCM I replaced all 4 O2 sensors with NGK and replaced both front cats.
P0057 is the only one left and i've gone through 3 PCM with @Wranglerfix

I'm gonna have an electrician come out and take a look at it because I got my smog requirement for my TJ this year in commiefornia. Only thing I can think of is some wiring is messed up somewhere.

If it doesn't work I'm going to be moving my TJs residence somewhere in Ca that doesn't require smog.
Click to expand...
If i had one code only and i knew that o2 was good and pcm was good. I would do a continuity check on each positive and neg heater circuit wire. Then a short to ground test. With o2 and pcm disconnected for that o2. See for how https://www.obd2-code.com/2017/06/p0051-o2-sensor-2-1-heater-circuit-low-jeep-chrysler.html
It seems daunting but i learned a ton doing it and all u need is a multimeter, some alligator clib battery wires. Some wiring diagrams from the fsm and patience

If any of those failed i would replace the ground and positive o2 htr circuit wires in the harness.
 
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robs559 said:
https://www.rubiconownersforum.com/...sions-4-o2-sensors.117309/page-2#post-1376431 has more info on my tale of woe. Dont know if its bad form posting another forum delete if it is. Just trying to get it sorted and share info.

Wranglerfix pcm seems to have caused those codes (31,37,51 ,57) to be resolved. Jeep runs better now getting actual error. New pcm got a p0431 and thats likely because my cat conv is gone.

All my research is pcm is a weak link here in the 05 06.

The downstream o2 sensors look more beat up than pam andersons diaphragm. Are you in california? Did you like that company for cats.

After changing my shorts looking at 3k carb compliant magna flow . Looking for a reasonably priced option for pipes / cats in CA
Click to expand...

Did you have an Auto or Manual tranny?

I have a 2005 manual LJ and have had similar codes for about 7 years now. They toggle on and off, mostly due to weather change. CEL on during the summer and off during the winter.

I had 032, 038, 052 and 058.

Since I am in an emissions states, the emissions test center said my PCM was bad so I gave in and ordered a new PCM from Wranglerfix. That didn't fix the problem but got rid of the codes and populated a 0431 code. I switched back to my stock PCM and I still have the P0431 code.

Aa you noted, a 0431 is a bad cat. Could a bad cat be the problem for all those codes? Maybe my cats went bad back in 2014???
 
Automatic. P0431 is most likely a bad cat but could have other electrical issues. You can pull the downstream o2 sensor on bank 2 rear precat. Look at it. If it looks more banged up than pam andersons diaphragm your cat is likely toast. If not you can put a camera in the o2 port and see how bad the cat looks. Many report replacing these precats 60 to 100k miles. You can also replace downstream o2 sensor see if it fixes it. The 02s probably should be replaced around 100k anyways.

I feel my pcm was bad and the wrangler fix pcm gave me the accurate code instead of those other codes that the cat is bad . Now looking for good california carb compliant precats that dont cost me my first born.
 
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Replaced cat with walker carb compliant cats and the p0431 code has not returned. So new pcm feel it was needed, Car ran better even without the new cat and gave the correct code which pointed me to the cat replacement. Also replaced the tranny mount, oss sensor, o2 sensors , spark plugs likely about 1700 in. But Jeep runs better than it ever has while Im driving it. Ill also say the rear cat has no o2 sensors and in ca on post 2000 vehicles they do no tail pipe tests. You do the math on that if your rear cat is plugged at all from front pre cat break up. Keep in mind your engine is an airflow device.
 
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robs559 said:
https://www.rubiconownersforum.com/...sions-4-o2-sensors.117309/page-2#post-1376431 has more info on my tale of woe. Dont know if its bad form posting another forum delete if it is. Just trying to get it sorted and share info.

Wranglerfix pcm seems to have caused those codes (31,37,51 ,57) to be resolved. Jeep runs better now getting actual error. New pcm got a p0431 and thats likely because my cat conv is gone.

All my research is pcm is a weak link here in the 05 06.

The downstream o2 sensors look more beat up than pam andersons diaphragm. Are you in california? Did you like that company for cats.

After changing my shorts looking at 3k carb compliant magna flow . Looking for a reasonably priced option for pipes / cats in CA
Click to expand...

Good information. My 06 unlimited has a long crank to start now. I got those four codes for the o2 sensors. I ve done new fuel pump ,new injectors, crankshaft sync. New plugs and new oem sensors. Still long crank. Ether pcm or upper cats are my last two options of being bad.
 
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