Is your Subaru’s battery mysteriously dying overnight? You might be dealing with the widespread DCM issue affecting hundreds of thousands of Subaru vehicles. This isn’t just a minor inconvenience – it’s left many drivers stranded with dead batteries and hefty repair bills. Let’s dive into what the Subaru DCM recall actually covers, which models are affected, and how to get your vehicle fixed.
What Is the Subaru DCM Recall?
Despite being commonly called a “recall,” this is technically a warranty extension program for faulty Data Communication Modules (DCMs) in Subaru vehicles. The DCM is the component that enables your car’s connectivity features through the STARLINK system.
The problem emerged when 3G networks shut down in early 2022, causing DCMs in affected vehicles to enter a continuous loop trying to connect to now-defunct cellular networks. This creates excessive battery drain (120-140 milliamps) that can completely discharge your battery overnight.
For context, a normal car should draw less than 50 milliamps when turned off. The DCM issue nearly triples this power consumption, which is why so many owners find their cars won’t start after sitting for just a day.
Which Subaru Models Are Affected?
The DCM warranty extension covers approximately 495,000 vehicles across multiple model years:
| Model | Years Affected | Estimated Vehicles Affected |
|---|---|---|
| Outback | 2016-2019 | 120,000 |
| Forester | 2016-2018 | 95,000 |
| Legacy | 2016-2019 | 85,000 |
| Impreza | 2016-2018 | 75,000 |
| Crosstrek | 2016-2018 | 70,000 |
| WRX | 2017-2021 | 40,000 |
| WRX STI | 2019-2021 | 10,000 |
The issue affects vehicles across two distinct groups:
- 2016-2018 models: Primarily affected by the 3G network shutdown
- 2019-2021 WRX/STI models: Experience DCM failures due to internal memory corruption, not network issues
How to Tell If Your Subaru Has a Faulty DCM
The most obvious sign of DCM failure is a battery that keeps dying despite being relatively new. Here are the common symptoms:
- Battery dies overnight or after short periods of non-use
- Vehicle starts normally but fails to start the next day
- Multiple battery replacements that don’t solve the problem
- Error code B2A0C (indicates DCM communication failure)
- STARLINK connectivity issues or errors on the infotainment screen
Many owners have replaced their batteries 2-3 times before discovering the DCM is the actual culprit. If you’ve experienced these symptoms, your vehicle likely needs DCM service under the warranty extension.
The Root Causes of Subaru DCM Failures
3G Network Shutdown
The primary trigger for widespread DCM issues was the retirement of 3G cellular networks by major carriers in February 2022. Older Subaru vehicles equipped with first-generation DCMs relied exclusively on 3G connectivity for STARLINK telematics services, including:
- Automatic collision notification
- SOS emergency assistance
- Remote vehicle features (lock/unlock, remote start)
When these networks went dark, the DCMs couldn’t adapt and entered a continuous search mode trying to find the network, draining the battery in the process.
Internal Memory Corruption
For 2019-2021 models, particularly WRX and STI vehicles, the problem stems from internal memory deterioration rather than network connectivity. These newer DCMs have 4G capability but suffer from hardware reliability issues affecting their memory systems, leading to similar battery drain symptoms.
How to Diagnose a Faulty DCM
While you can suspect DCM issues based on symptoms, professional diagnosis requires specialized equipment:
- Parasitic draw testing: Using a multimeter to measure electrical current consumption when the vehicle is off
- Signal strength verification: Checking if the DCM can establish a connection
- Error code scanning: Looking for specific trouble codes related to the DCM
Subaru dealerships follow specific diagnostic protocols outlined in Technical Service Bulletin 15-308-23, which requires confirming both DCM signal strength and subscription status.
Available Repair Solutions
1. Complete DCM Replacement
This is the most comprehensive solution, providing:
- 95% effectiveness in resolving battery drain
- Maintains all vehicle features
- Costs $800-$1,200 (covered under warranty extension)
This option is ideal for vehicles with active STARLINK subscriptions and ensures long-term reliability.
2. DCM Bypass Box Installation
For vehicles without active STARLINK subscriptions:
- 90% effective in eliminating battery drain
- Retains essential functions (speakers, microphone)
- Costs $400-600 (covered under warranty)
- No longer the preferred solution as of 2025
3. DIY Temporary Fixes
While waiting for a dealer appointment:
- Fuse removal (fuse #9): Completely eliminates battery drain but disables Bluetooth and front speakers
- Factory reset: Resolves some DCM issues temporarily (60% effective)
- Battery disconnect: Works but requires resetting vehicle electronics each time
What the Warranty Extension Covers
Subaru has dramatically extended the DCM warranty coverage from the original 3 years/36,000 miles to 8 years/150,000 miles for affected vehicles. This extension applies automatically regardless of:
- Current mileage
- Original warranty status
- Vehicle ownership history
The warranty extension specifically covers:
- DCM replacement or bypass box installation
- Battery testing and replacement (when DCM-related)
- Software updates for vehicles with active STARLINK subscriptions
How to Get Your Subaru Fixed
- Contact your Subaru dealer to schedule a diagnostic appointment
- Mention the DCM warranty extension specifically (reference TSB 15-318-24R)
- Provide your VIN number to confirm eligibility
- Request a loaner vehicle if available, as repairs can take 1-2 days
If your vehicle is confirmed to have DCM-related battery drain, the dealer will perform the necessary repairs at no cost under the warranty extension.
Reimbursement for Previous Repairs
If you’ve already paid for DCM-related repairs, you may qualify for reimbursement. Eligible expenses include:
- Previous DCM replacement costs
- Battery replacements caused by DCM failure
- Diagnostic fees related to DCM issues
The reimbursement process requires:
- Repair receipts
- Proof of payment
- Vehicle identification information
Submit your claim through Subaru’s dedicated claims website or by mail following the instructions provided in your warranty notification.
The Timeline of Subaru’s Response
The DCM issue has evolved over several years:
- 2016-2018: Initial DCM issues emerge with relatively low impact
- February 2022: 3G network shutdowns trigger widespread battery drain problems
- April 2023: Subaru releases Technical Service Bulletin 15-318-24R
- February 2024: Formal warranty extension announcement
- April 2024: Update to include bypass box installation options
- February 2025: Prioritized DCM replacement as parts availability improved
The extended warranty period provides significant coverage, but it’s important to address this issue promptly rather than continuing to replace batteries.
Understanding the Technical Repair Process
When you bring your vehicle to the dealer, here’s what happens during the repair:
- Diagnostic testing: Parasitic draw measurement and error code scanning
- Component access: Removal of interior panels to reach the DCM (varies by model)
- DCM replacement: Installation of new DCM unit with updated software
- Battery testing: Verification of battery condition and replacement if necessary
- System testing: Confirmation that parasitic draw has returned to normal levels
The procedure varies by vehicle model. Legacy and Outback vehicles require removal of center grille assembly and heater controls to access the DCM, while WRX models involve removal of knee airbag modules and glove box assemblies due to different mounting locations.
Beyond the DCM: Protecting Your Subaru’s Battery
While fixing the DCM addresses the root cause, these additional steps can help maintain battery health:
- Regular driving: Try to drive your vehicle at least once a week for 30+ minutes
- Battery maintenance: Clean terminal connections and check for corrosion
- Consider a trickle charger: For vehicles stored for extended periods
- Battery health testing: Have your battery tested annually, especially before winter
These practices can extend battery life and provide early warning of potential issues.
Customer Support Resources
Subaru has established dedicated support channels for DCM-related issues:
- Warranty extension hotline: 877-551-7149
- Online claims portal: subaruclaims.autosolutionteam.com
- Dealer network: All authorized Subaru dealers can perform the repairs
When contacting customer support, have your VIN ready and specifically mention the DCM warranty extension program to expedite service.
The Bigger Picture: What This Means for Connected Cars
The Subaru DCM issue highlights the challenges of connected vehicle technology, particularly when telecommunications networks evolve. As vehicles become increasingly connected, similar issues may affect other manufacturers when networks change from 4G to 5G and beyond.
This case demonstrates the importance of:
- Future-proofing automotive technology
- Providing clear upgrade paths when networks change
- Maintaining customer support for connected features
While Subaru’s warranty extension provides necessary protection for current owners, it also reveals how dependent modern vehicles have become on reliable connectivity infrastructure.
Taking Action: Next Steps for Subaru Owners
If you own an affected Subaru model, don’t wait for battery failure to act:
- Check your VIN on Subaru’s recall lookup page
- Document any symptoms you’ve experienced (dates, conditions, repair attempts)
- Contact your dealer to schedule diagnosis and repair
- Keep records of all communications and repair attempts
Even if your vehicle isn’t currently experiencing symptoms, having the DCM inspected can prevent future battery failures and potentially dangerous situations where your vehicle won’t start.
The DCM issue may seem like a minor inconvenience, but it affects critical features including emergency response systems. Addressing it promptly ensures both your convenience and safety on the road.
