Chrysler Repair: Reoccurring P0138 code on 1998 plymouth Grand Voyager, plymouth grand voyager, grand voyager

Question
I have a 1998 Plymouth Grand Voyager , and I replace the O2 sensor when
my van Check Engine Soon Light pop on with code P0138. Few days later it
pop on with the same code so I took it in, and they check the wire, and cat
back and they change the O2 sensor again and off I went again. A few day
later the code pop on again, and I am at a lost for why I am having this P0138
code. I now just reset the PCM with the code scanner , and I am good to go
for a few week. Do you have any idea what maybe causing this, because ever
one at a lost

Answer
everyone is at a loss because they dont know how to correctly diog something after a parts change.


POSSIBLE CAUSES
1/2 O2 SENSOR SIGNAL CIRCUIT SHORT TO VOLTAGE
1/2 O2 SEN HARNESS INTERMITTENT SHORT TO VOLTAGE
1/2 O2 SENSOR CONNECTOR OBSERVABLE DEFECT (A)
1/2 O2 SENSOR CONNECTOR OBSERVABLE DEFECT (B)
1/2 O2 SENSOR HARNESS OBSERVABLE DEFECT
1/2 O2 SENSOR DEFECTIVE