Emissions - MIL ON/DTC P0420 (Catalyst Efficiency)
03-027November 21, 2003
Applies To:
1999 3.2TL - ALL
MIL Is On With DTC P0420
(Supersedes 03-027, dated October 31, 2003)
Updated information is shown by asterisks.
SYMPTOM
The MIL is on, and DTC P0420 (catalyst system efficiency below threshold) is stored.
PROBABLE CAUSE
The catalytic converter has deteriorated.
CORRECTIVE ACTION
Replace the catalytic converter, and check or any related DTCs.
PARTS INFORMATION
WARRANTY CLAIM INFORMATION
In warranty: The normal warranty applies.
NOTE:
Catalytic converters are covered by the 8/80 Federal and California emissions warranties.
Failed Part: P/N 18160-P8C-A00
*Defect Code: 01102
Symptom Code: 03203*
Skill Level: Repair Technician
Out of warranty: Any repair performed after warranty expiration may be eligible for goodwill consideration by the District Parts and Service Manager or your Zone Office. You must request consideration, and get a decision, before starting work.
DIAGNOSIS
Connect the HDS to the DLC (data link connector) and read the stored DTC(s).
^ If DTC P0420 is the only code, go to REPAIR PROCEDURE.
^ If other DTCs are stored along with P0420 troubleshoot those codes first. Failure of other components could contribute to the failure of the catalytic converter, and could cause it to fail again. Then go to REPAIR PROCEDURE.
REPAIR PROCEDURE
1. *Determine the emissions type (KA or KL) of the vehicle. Either do a VIN Status Inquiry on iN, or examine the catalytic converter. On a KA emissions type vehicle, the secondary oxygen sensor is in the rear of the converter. On a KL emissions type vehicle, the oxygen sensor is in the middle of the converter*.
2. Replace the catalytic converter. If the mounting bolts do not break due to corrosion when you remove the original upper and lower covers, then reuse the covers. Otherwise, replace the covers and the mounting bolts.