Toyota Sienna 2001–2003 — technical service bulletin
Bulletin 04705 · NHTSA communication 10017659 · issued Oct 19, 2005
Technical service bulletin
communication type
Engine and Engine Cooling
component
2001–2003
model years
3
vehicle entries
Official summary
Malfunction indicator lamp on diagnostic trouble code p0420. *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.