Subaru bulletin 15-318-24
What it saysThis bulletin announces the availability of a Data Communication Module (DCM) bypass box. NHTSA’s full summary ↓
Subaru filed this with NHTSA as a service bulletin dated Feb 23, 2024, received Mar 4, 2024, about the electrical system. It names 5 model years (2019–2021). A service bulletin is not a safety recall: it is the manufacturer telling its dealers how to diagnose or repair a condition, and whether the work is paid for depends on the warranty in force. Quoting the number at a service desk can save a diagnosis.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationThis bulletin announces the availability of a Data Communication Module (DCM) bypass box. This has been designed as an alternative replacement part for vehicles without active STARLINK subscriptions. The bypass box will support audio functions for the infotainment system.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| 15-318-24 | Service bulletin | Feb 23, 2024 | 10251102 | PDF, 2,322 KB |
What the document itself lists
The manufacturer titles it “Data Communication Module (DCM) Bypass Box”.
Part the bulletin names
| Part number | Description | Qty | Find it |
|---|---|---|---|
| 86229AL400 | DCM BYPASS BOX | — | eBay Motors → |
Read by machine from the document NHTSA serves (14 pages), read Sep 30, 2026. A part number is shown only where it matches Subaru’s own catalogue shape, an operation only with its code and time, and a description only where the reader got it whole; anything it could not settle is left out, and the PDF is the record. Times are the manufacturer’s warranty allowances, not a quote. Listings and prices on eBay Motors are the seller’s.
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The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themA vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
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What owners reported
Source: NHTSA complaint databaseOwners of the 5 model years this bulletin names have filed 1,221 complaints with NHTSA since 2015. 425 of them name Electrical System — the same broad component group this bulletin is filed under. NHTSA groups complaints coarsely, so that means the same area of the vehicle, not necessarily the same fault.
On the 2019 Subaru Outback, the 104 owners who gave an odometer reading for Electrical System reported it at a median of 13,563 miles. That figure is one model year’s, not the whole range this bulletin covers — medians from different model years are not averaged.
While backing out of my garage, the radio unit froze making the backup screen inoperable. This is a brand new car with 200 miles on it. According to the dealer, they will have to replace the head unit. They were able to get the unit working, hopefully until the new head unit arrives, by physically disconnecting the car battery.
2019 Subaru Outback · Electrical System · filed with NHTSA Jun 6, 2019 · ODI 11218229
Parasitic battery problem My car battery keeps dying on my Subaru sti 2020 after one day of not driving. I have had the car checked with Subaru dealership and a local shop but no issues were found. This morning I had to get my car jumped again after not driving it for one day. This battery was purchased brand new on nov 2024.
2020 Subaru WRX · Electrical System · filed with NHTSA Jan 7, 2025 · ODI 11634545
There is a current drain (approximately 135mA) by the built-in telematics system (DCM) even when the car is completely powered off. The drain will drop battery voltage levels beyond recharge/repair.
2019 Subaru WRX · Electrical System · filed with NHTSA May 1, 2023 · ODI 11519850
In depth: 2019 Subaru Outback electrical problems →
A complaint is one owner’s account, not a defect finding, and a bulletin is not a recall. Nothing here says this bulletin was issued because of these complaints, or that the repair it describes fixed them. Complaint files on this site begin in 2015.
More bulletins about the electrical system
Source: same model, same component group105 other manufacturer communications filed against these Subaru models under the same component group (electrical system), newest first. The eight newest are listed; the rest are on the Subaru list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| 18-244-26 | Service bulletin | Sep 18, 2026 | "This Bulletin announces additional troubleshooting steps for the following DTCs: DTC C1956: RH Actuator Circuit DTC C1957: LH Actuator Circ… |
| 15-333-25R | Service bulletin | Sep 14, 2026 | This bulletin contains illustrations of exchange components and their manufacturer as well as a description of the proper exchange procedure… |
| 15-331-25R | Service bulletin | Sep 14, 2026 | This Bulletin has been developed to outline the steps for gathering basic but essential information during diagnosis of Infotainment concern… |
| 15-322-25R | Service bulletin | Sep 14, 2026 | In the interest of customer satisfaction, Subaru of America, Inc. (SOA) is extending the New Car Limited Warranty coverage for the CP1 & Gen… |
| 15-304-22R | Service bulletin | Sep 14, 2026 | This Bulletin has been developed to outline the steps for gathering basic but essential information during diagnosis of Infotainment concern… |
| 15-343-26 | Service bulletin | Sep 1, 2026 | "This bulletin announces a design change to the cord assembly that connects the Center Infotainment Display (CID) to the CCU, addressing rep… |
| 15-342-26 | Service bulletin | Aug 31, 2026 | This bulletin announces an inspection procedure for the Smart Rear View Mirror Assembly. |
| 15-261-20R | Service bulletin | Aug 31, 2026 | This bulletin announces reprogramming file availability and provides a software update installation procedure to optimize the new Gen 4 Dens… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Subaru, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Subaru 15-318-24 a recall?
No. A service bulletin is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the 15-318-24 repair free?
Not automatically. A service bulletin describes how to diagnose or repair a condition; who pays depends on the warranty in force, any extension, and the dealer. Quoting the number can save a diagnosis either way. Every Subaru warranty extension on file lists the ones Subaru has filed.
Which vehicles does 15-318-24 cover?
The manufacturer filed it against 5 model years: 2019 Subaru Legacy, 2019 Subaru Outback, 2021 Subaru WRX, 2020 Subaru WRX, 2019 Subaru WRX. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.