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Service bulletin AA0H0

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10184801
Published by NHTSA2020-12-28
Manufacturer's numberAA0H0
Manufacturer's date2015-07-01
NHTSA componentENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM):SOFTWARE

NHTSA's summary

ECU False P0421 DTC Detection. A subject vehicle may exhibit an illuminated MIL (Malfunction Indicator Lamp) with DTC (Diagnostic Trouble Code) P0421 (ATC Dtc Deterioration Monitoring). The engine ECU may falsely detect an issue with the ATC ( After Turbo Catalyst). Enhanced ECU software is available.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine, Engine control module

Trouble codes named

P0421

Vehicles listed
HINO CONVENTIONAL TRUCKS W/JO82015

Listing a model year does not mean every vehicle of it is concerned: the document says which.