Code Enable Criteria

WARNING: This page is about a different car, the 2002 Isuzu Trooper. However, it is still accessible from the selected car via links, so may be relevant.

Following conditions must be met for DTC diagnostic test to run:

Engine has been running for 120 seconds or more.
HO2S heater signal is less than 0.1 amps.
Bank 2 HO2S No. 1 voltage does not change more than 150 millivolts from bias voltage (between 400 and 500 millivolts) for a longer amount of time than necessary. Maximum amount of time to come up to operating range is 150 seconds. Warm-up time depends on engine coolant temperature at start-up and accumulated air flow since start-up.