2004 Yukon Denali XL - new cats & rear HO2Ss Now P0141 & P0161

[W M S]

Hi, new here, but not new to these wonderful machines that can be so challenging.

Anyway, previous to repairs, P0420 & P0430 were set.

I replaced both the cats and rear HO2Ss (AC Delco 213-3867 | specified replacements for the OEM sensors), they had over 150k miles and 18 years on them.

The cat monitors/DTCs haven't run/passed, because P0141 & P0161 have failed.

P0141 & P0161 are the O2 Sensor Heater Circuit Malfunction codes for B1S2 and B2S2, and they did not set before the new HO2Ss were installed.

Has anyone come across this?

 

[W M S]

I installed the old (Delphi - OEM?) B1S2 & B2S2, and ran the Yukon.

No P0141 & P0161.

I looked closely at the new AC Delco sensors and found the pins for the heaters had backed out. Re-seated them, reinstalled and all is good.