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Service bulletins for the 2021 Subaru Ascent

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.

384 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
15-256-19R2024-02-02. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT; EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM); EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. This bulletin provides information on a new reprogramming procedure (FOTA) to optimize the Harman Gen 3.1 Audio and Navigation head units (H/U) utilized in the models as listed.
15-236-18R2024-01-03. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. The following information addresses reprogramming file availability and a software update installation procedure to provide optimization to the new Harman Gen 3.1 Audio and Navigation head units utilized in the models as listed.
18-232-232023-12-05. Service bulletin. ELECTRICAL SYSTEM. This Service Information Bulletin announces the revised break-in procedure for the A/C compressor.
12-251-232023-12-05. Service bulletin. STRUCTURE:BODY:HATCHBACK/LIFTGATE; LATCHES/LOCKS/LINKAGES; ELECTRICAL SYSTEM. This bulletin announces the initialization service procedures to be followed when diagnosing and/or repairing Power Rear Gate (PRG) systems.
16-144-232023-12-05. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM. This bulletin announces the availability new service procedure developed for the diagnosis of the following DTCs detected by the Transmission Control Module (TCM):
12-252-23R2023-11-06. Service bulletin. SEATS; ELECTRICAL SYSTEM. This bulletin announces the availability of new seat ventilation blower units.
18-225-22R2023-11-06. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT:ELECTRICAL:INFOTAINMENT; EQUIPMENT. This Service Bulletin is to inform you of the diagnosis procedure of the Harman Infotainment System when DTC B2255 is detected.
15-266-20R2023-11-06. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT; COMMUNICATION:MANUFACTURER TELEMATICS. This Bulletin provides helpful procedures and best practices to utilize when customers present with concerns relating to the operation of their Gen 2/Gen 3 Telematics system equipped Subaru.
07-219-23R2023-11-06. Service bulletin. ELECTRICAL SYSTEM. This bulletin announces availability of a new Genuine Subaru Alternative Replacement Battery introduced to satisfy current supply demands.
15-236-18R2023-11-06. Service bulletin. EQUIPMENT; EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM); ELECTRICAL SYSTEM. The following information addresses reprogramming file availability and a software update installation procedure to provide optimization to the new Harman Gen 3.1 Audio and Navigation head units utilized in the models as listed
16-140-232023-10-03. Service bulletin. POWER TRAIN; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); ELECTRICAL SYSTEM. This bulletin announces availability of new reprograming files for the Transmission Control Module (TCM) to address judder a sensation possibly accompanied by a vibration-type sound when accelerating from slow speeds.
18-231-232023-10-02. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM; FORWARD COLLISION AVOIDANCE. This Bulletin announces additional information regarding error codes 1403- 1407 encountered when attempting an adjustment/calibration of the EyeSight® system after body repair procedures have been performed.
15-282-21R2023-09-05. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT; ELECTRICAL SYSTEM. This Service Information Bulletin announces additional diagnostic procedures and a detailed flow chart to be used when diagnosing customer concerns regarding the operation of the STARLINK Remote Engine Start (RES) feature.
07-219-23R2023-09-05. Service bulletin. ELECTRICAL SYSTEM:12V/24V/48V BATTERY; ELECTRICAL SYSTEM. This bulletin announces availability of a new Genuine Subaru Alternative Replacement Battery introduced to satisfy current supply demands.
01-168-09R2023-09-05. Service bulletin. LATCHES/LOCKS/LINKAGES; EQUIPMENT; ELECTRICAL SYSTEM. The purpose of this bulletin is to provide replacement key and immobilizer information along with an overview of the Subaru Lock Information web-site.
15-304-22R2023-08-02. Service bulletin. EQUIPMENT:ELECTRICAL:INFOTAINMENT; EQUIPMENT; ELECTRICAL SYSTEM. This Service Information Bulletin has been developed to outline the steps for gathering basic but essential information during diagnosis of Infotainment concerns.
16-141-23R2023-08-02. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:PROPULSION SYSTEM:TRACTION BATTERY:THERMAL MANAGEMENT:FLUID/COOLANT; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); ELECTRICAL SYSTEM. This bulletin announces availability of reprogramming files to optimize the Transmission Control Module (TCM). The new files were designed to address cases of DTC P0711 (Transmission Fluid Temperature Sensor “A” Circuit Range/Performance) being detected by the TCM during low ambient temperatures (32° F(0° C)).
09-107-232023-08-02. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM):SOFTWARE; ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This bulletin announces diagnostic procedures and availability of new Engine Control Module (ECM) reprogramming files to address DTC P2404 (Evap System Leak Detection Pump Sense Circuit Range/Performance) detection.
15-285-21R2023-08-02. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT:ELECTRICAL:INFOTAINMENT; EQUIPMENT:ELECTRICAL:INFOTAINMENT:SOFTWARE; EQUIPMENT. This Bulletin provides reference tables and photos to use for determining the infotainment head unit supplier and generation.
15-240-19R2023-07-03. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This bulletin announces availability of new Harman audio unit amplifier units with revised internal logic designed to optimize efficiency while addressing customer concerns.
16-132-20R2023-07-03. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM. This Service Information 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 used in the models listed.
15-236-18R2023-07-03. Service bulletin. EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM); ELECTRICAL SYSTEM:SOFTWARE; ELECTRICAL SYSTEM. The following information addresses reprogramming file availability and a software update installation procedure to provide optimization to the new Harman Gen 3.1 Audio and Navigation head units utilized in the models as listed.
15-300-22R2023-07-03. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM; EQUIPMENT; COMMUNICATION:MANUFACTURER TELEMATICS. This Service Information Bulletin provides the diagnostic procedure for the STARLINK® Remote Engine Start (RES). All Gen2 and Gen3 Telematics Equipped Models.
07-219-23R2023-06-05. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This bulletin announces availability of a new Genuine Subaru Alternative Replacement Battery introduced to satisfy current supply demands.
15-255-19R2023-06-05. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM; EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM). Map Data Update Procedure for Harman Gen 3.1 Navigation Equipped Head Units (H/U).

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.