P0430: Catalyst System Efficiency Below Threshold (Bank 2)
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P0430 - CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD (BANK 2)
| Description: | Indicates the bank 2 catalyst system efficiency is below the acceptable threshold. | ||
| Possible Causes: | See the possible causes for DTC P0420. | ||
| Diagnostic Aids: | Compare HO2S upstream (HO2S21) and downstream (HO2S22) switch rate and amplitude. Under normal closed loop fuel conditions, high efficiency catalysts have oxygen storage which makes the switching frequency of the downstream HO2S very slow and reduces the amplitude of those switches as compared to the upstream HO2S. As catalyst efficiency deteriorates, its ability to store oxygen declines and the downstream HO2S signal begins to switch more rapidly with increase amplitude, approaching the switching rate and amplitude of the upstream HO2S. Once beyond an acceptable limit the DTC is set. | ||
| Application | Key On Engine Off | Key On Engine Running | Continuous Memory |
| All | - | - | GO to PINPOINT TEST HF: CATALYST EFFICIENCY MONITOR AND EXHAUST SYSTEMS Step 1. |