Honda Civic 1999–2000 — technical service bulletin
Bulletin 011001 · NHTSA communication 627496 · issued Oct 1, 2001
Technical service bulletin
communication type
Electrical System
component
1999–2000
model years
2
vehicle entries
Official summary
Subject regarding diagnostic trouble code p9999 probably being diagnostic trouble code p0420. *slc
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.