2005 Wrangler O2 sensor code trouble troubleshooting (P0135 and P0155)

[3521inapastlife]

I've gone through the other threads, but couldn't find something on this guy.

I've gotten this from an insurance auction and have gotten everything fixed aside from the two P0135 and P0155 codes. These are both upstream 02 sensor heating codes. I've replaced the sensors, straight from the Chrysler dealership, and checked the harness (no breaks or grounding issues). Aside from splicing a voltmeter into the circuit, I'm lost as to what the issue could be.

I really don't want to resort to purchasing a new PCM, but it looks like this might be the only solution left.

It is a 2005 X 4.0 inline 6.

 

[SoCalGlide]

I believe there is a TSB on that. Check this thread, there are links to more info.
https://wranglertjforum.com/threads/sb-25-001-07.1703/

 

[3521inapastlife]

I believe there is a TSB on that. Check this thread, there are links to more info.
https://wranglertjforum.com/threads/sb-25-001-07.1703/

Not quite the same issue, but definitely could be the problem.
I love TSBs. Thanks for the info, I'll have to check this out.

 

[Jerry Bransford]

@Wranglerfix may have a comment to add on your O2 sensor problem.

 

[Wranglerfix]

@3521inapastlife

One of the symptoms of a failing pcm is faulty 02 sensor readings...Are you having any other issues with the pcm such as high transmission temps or hard shifts from 1st to 2nd when cold?

You can call me to discuss in further detail at 866-888-7710.

Have a great day in Maricopa County and I look forward to hearing from you.

Mark

 

[3521inapastlife]

@3521inapastlife

One of the symptoms of a failing pcm is faulty 02 sensor readings...Are you having any other issues with the pcm such as high transmission temps or hard shifts from 1st to 2nd when cold?

You can call me to discuss in further detail at 866-888-7710.

Have a great day in Maricopa County and I look forward to hearing from you.

Mark

I am not. It's a manual, so no shift issues. I did the TSB and it actually brought up another (slow O2 reading) code (P0153 I believe). I'm currently swapping the O2 sensors to the suggested NTK/NGK so hopefully that'll do the trick.
Just got it certed by the state road inspectors, so the only obstacle is the emissions check. Crossing my fingers.

Thanks again for all the help!

-Steve

 

[3521inapastlife]

Ok, so, replaced all 4 O2 sensors (just in case) with the proper NTK sensors, and it's still throwing a pending/saved code for P0135/155 heater circuit. Performed the TSB, which I'll have to throw on here (I wrote tech manuals for John Deere, so I took some pics as I went along in case anyone in the future needed to do it, I hope they don't).

Any input would be greatly appreciated. Otherwise I'm going to submit and go to the dealership (shame shame).

My last resort is the PCM, but I'd rather not shell out 700-1200 for a new one, but that's all I can figure is left to do.

-Steve

 

[3521inapastlife]

@3521inapastlife

One of the symptoms of a failing pcm is faulty 02 sensor readings...Are you having any other issues with the pcm such as high transmission temps or hard shifts from 1st to 2nd when cold?

You can call me to discuss in further detail at 866-888-7710.

Have a great day in Maricopa County and I look forward to hearing from you.

Mark

If I recall correctly, you have a company that sells PCM's? I can't find the link to it anymore. I'm finally in a place I can afford this purchase.

 

[Wranglerfix]

Call me at 866-888-7710 option 1.