LEMON Manuals
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Jaguar
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2002
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XKR Base, 2D Convertible
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Repair and Diagnosis
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Engine Performance
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System
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Engine Controls - Self-Diagnostics
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Diagnostic Trouble Code Identification
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DTC P0420: Catalyst Efficiency Below Threshold (Bank 1)
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Possible Causes
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Possible Causes
HO2S disconnected.
HO2S to ECM wiring fault.
HO2S heater to ECM wiring fault.
HO2S heater failure.
Upstream HO2S failure.
Downstream HO2S failure.
Catalyst failure.