Toyota Sienna 1999 — technical service bulletin
Bulletin 031199 · NHTSA communication 605187 · issued Mar 11, 1999
Technical service bulletin
communication type
Unknown OR Other
component
1999
model years
1
vehicle entries
Official summary
Brief information regarding diagnostic trouble code p0420 indicating a possible catalyst system efficiency below threshold condition. *tt
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.