LEMON Manuals
: Even more car manuals for everyone: 1960-2025
Home
>>
Jaguar
>>
2003
>>
XJ8 SC
>>
Repair and Diagnosis
>>
Engine Performance
>>
System
>>
Engine Controls - Self-Diagnostics
>>
Diagnostic Trouble Code Identification
>>
DTC P0420: Catalyst Efficiency Below Threshold (Bank 1)
>>
Possible Causes
July 1:
So it begins
. Don't worry, this is not in the correct legal jurisdiction!
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.