WenmarOpen by Wenmar Pro

Service bulletin WTT-79R

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 id10144878
Published by NHTSA2018-10-01
Manufacturer's numberWTT-79R
Manufacturer's date2018-08-29
NHTSA componentPOWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); EQUIPMENT:APPLIANCE:AIR CONDITIONER; ENGINE

NHTSA's summary

Subaru of America, Inc. (SOA) is initiating a service program for certain 2017-2019 MY Impreza vehicles, and certain 2018-2019 MY Crosstrek vehicles. This service program involves installation of reprogramming files to optimize the ECM. Subaru has determined that due to an engine programming issue, the affected vehicles may stall when coming to a stop or driving at a low speed (under 15 MPH) when the air conditioning is operating at maximum capacity. Under certain hot weather conditions, when the vehicle?s air conditioning is running at full capacity, the engine programming may not account for the additional load placed on the engine when slowing down or coming to a stop. In some cases, this could cause the engine to stall requiring the driver to immediately restart the vehicle.

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, Equipment and accessories, Heating and air conditioning, Transmission and driveline, Automatic transmission, Transmission control module

Vehicles listed
SUBARU CROSSTREK2018, 2019
SUBARU IMPREZA2017, 2018, 2019

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

Other bulletins for the same vehicles and component
16-136-22R2023-07-03. Service bulletin. This service bulletin provides a temporary repair procedure to address vibrations and/or judder concerns experienced on turns during acceleration.
16-132-20R2022-02-04. Service bulletin. This bulletin provides updated diagnostic procedures to follow and a brief questionnaire to complete when diagnosing an alleged Chain Slip condition on the TR580 and TR690 model CVT transmissions.
16-111-18R2019-03-25. Service bulletin. This bulletin announces reprogramming file availability to optimize the Transmission Control Module (TCM) used with the TR580 CVT. Contamination in a fluid pressure solenoid valve can cause a DTC P0841. The new logic will allow the solenoid to operate in a manner enabling it to discharge the contamination.
WTT-792018-10-01. Service bulletin. Subaru of America, Inc. has initiated a service program for certain 2017?2019 MY Impreza vehicles, and certain 2018?2019 MY Crosstrek vehicles. This service program involves installation of reprogramming files to optimize the ECM.