Service bulletin TC-12-028

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)
Type	Service bulletin
NHTSA id	10134032
Published by NHTSA	2018-04-23
Manufacturer's number	TC-12-028
Manufacturer's date	2012-10-03
NHTSA component	ENGINE

NHTSA's summary

In certain 2011 and 2012 Model Year Toyota Corolla vehicles manufactured at TMMMS, the Positive Temperature Coefficient (PTC) Heater relays were not installed.

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

Vehicles listed
TOYOTA COROLLA	2011, 2012

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

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