oxygen sensor on 2004 Toyota 4Runner

check engine light, vsc trac and trac off lights all on,dealer claimed that it's for the oxygen sensor failed, it'll cost me around 400+,but the part is nationwide backordered. My question is why all lights on only due to oxygen sensor failed?? I had my car repaired 2 months ago for the catalytic converter replaced, the vsc trac & trac off lights all on as well at that time. Will it related to previous repair? I paid over 2,000 for that repair.

Asked by for the 2004 Toyota 4Runner
The O2 sensor may have been marginal at that time, it is usually the heater circuit in the sensor that fails. the sensor is certainly available from other sources than the dealer at a cheaper price. Denso or NGK make really good sensors for I would guess $140 and 1 hour to install, .3 hour to clear codes and road test.
Many sensors share information with several computers in your car that is why a fault in one item often triggers several lights.