R/L Status Bank 1 Sen 3

Need a step-by-step guide?

Get an AI-powered repair guide with parts lists, cost estimates, and clear instructions for your 1999 Cadillac.

AI Repair Guides
Display shows Rich or Lean. This represents the POST HO2S in the catalyst monitor (located downstream of the catalyst). Display should change much slower when compared to the Bank 1 and Bank 2 fuel control sensors indicating the catalyst is operating efficiently.