02 sensor troubles?

JEFF HARLEY

MEMBER
2015 FORD EXPLORER
3.5L
V6
TURBO
4WD
AUTOMATIC
120,000 MILES

I have the vehicle listed above Sport with a 3.5l turbo. I had multiple o2 sensor codes for b1s1 and found some chewed wires. Repaired the wires and then had an o2 code for p0135. I replaced the o2 sensor and now have a p2243 code for O2 sensor reference voltage to the sensor is open. I was hoping for some advice. Maybe a wiring diagram for the b1s1 location. The explorer is a 2015 but has the 198 pin PCM like the one pictured.

Image (Click to make bigger)

Tuesday, September 27th, 2022 AT 1:12 PM

3 Replies

JACOBANDNICKOLAS

MECHANIC
110,077 POSTS

Hi,

Is the P0135 still present? If it is, we have to start there. However, since the sensor is new, I have a feeling there is still a broken wire to it.

The up and downstream sensors get power from fuse 67 in the battery junction box. Since the code is specific to the one upstream, the fuse can't be the issue.

I attached the wiring schematic below and highlighted the wires relevant to the O2 sensors. Let me know if they help. I would check for power to the solid green wire at the sensor.

Note: The schematic for the powertrain control circuit is seven pages long. I had to cut each page in half to make them readable. I did overlap them for you so they can be
followed.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-wiring

Let me know what you find.

Take care,

Joe

See pics below.

Images (Click to make bigger)

Was this

answer

helpful?

Yes

No

Tuesday, September 27th, 2022 AT 7:56 PM

JEFF HARLEY

MEMBER
6 POSTS

Thank you so much for the help. The p0135 code was gone. I checked for continuity between the PCM and the 02 sensor plug and everything was good. I reinstalled the old o2 sensor and everything seems to be working. I'm a little confused at this point, but I'll take working, lol.

Was this

answer

helpful?

Yes

No

Sunday, October 2nd, 2022 AT 8:28 AM

JACOBANDNICKOLAS

MECHANIC
110,077 POSTS

Hi,

You are very we, come and thank you for the update. I'm glad to know it's working properly again. You likely had a bad or weak connector.

If anything changes, let me know. Also, please feel free to come back anytime in the future. You are always welcome here.

Take care,

Joe

Was this

answer

helpful?

Yes

No

Sunday, October 2nd, 2022 AT 9:10 PM