2003 Ram 1500 V6 P0141 Recurring issues!

[JimmyJimJims]

Hello! I'm new here but my problem sure isn't lol, a few years ago I bought a 2003 Ram 1500 quadcab 2WD 3.7L v6 with 149000 miles from a dealer in town. When purchased the dealer said "just needs an o2 sensor" which is code for has 12 more hidden trouble codes AND needs an o2 sensor :/ so those were all fixed, new upper and lower NTK oxygen sensors and a new Magnaflow catalytic converter (my truck only has the 1 cat and 2 sensors) plus a host of other new parts and for a year I had NO check engine light. About 4 months ago it popped back on one day with P0141 "Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2" so it was AGAIN replaced with a new Denso sensor this time. CEL cleared annnnd 2 days later P0141 AGAIN! So this time I checked the ohms on the new downstream sensor and the sensor had a reading of 7.1 ohms, well within the spec for a new downstream o2, aka the sensor is fine and working. So why the CEL? Is there something else that can go wrong on these trucks besides the actual o2 sensor itself causing a P0141? Wiring? Is there a way to check? Thanks in advance this has me confused as heck

Truck runs just fine otherwise, only has the 1 code, any ideas?

 

[DCMojoJim]

Sounds like the post I just put up for my
2004 5.8 L 1500 w/ only 52,000 mi
Replaced O2 sensors (2X) and code returns P0141
Bank 1 sensor 2 heater failure
Checked sensor @ 6 Ohms resistance and power to sensor unit running 13.6 V
Engine runs fine on (closed loop) but kicks up code when switching over.
Need it to function to pass inspection (failed to to monitor not ready)
Checked Temp pre cat @ 450 and post cat is 410 ( does that mean a Bad Catalytic converter ? )
Replaced Plugs, Coils, wires, up stream O2 sensor 3 years and 5k mi ago .
Was thinking of chasing wire to PCM for short , but I'm getting readings on OBD
Any sage mechanical advise on what to check or replace next ?
Do you remember how you got to the fix ?

 

[DCMojoJim]

OK , Follow up here , The cure is not to use Amazon fits all 4 for $50 O2 sensors
Use $100 rear and $60 front NTK/NGK sensors and problem is solved