What goes wrong
Owners may find their Crosstrek with a completely dead battery, especially after the vehicle sits for an extended period (e.g., overnight or a few days). This parasitic draw occurs when an electrical component continues to consume power even when the vehicle is turned off, slowly draining the battery until it can no longer start the car.
Symptoms to watch for
- Dead battery after sitting overnight or for a few days
- Difficulty starting the vehicle
- Battery warning light illumination (after jump start)
- Starlink system not functioning correctly
Root cause
The primary culprit is often the Data Communication Module (DCM), which is integral to the Starlink telematics system. A software glitch or an internal fault within the DCM can prevent it from entering a low-power "sleep" mode, leading to a constant draw on the battery even when the ignition is off. Other less common causes include aftermarket accessories, faulty relays, or a failing alternator diode.
Buy time with these
- • Disconnecting the negative battery terminal if the car will be sitting for an extended period (not recommended long-term due to loss of ECU learning and clock settings).
- • Using a trickle charger if the vehicle is parked for long durations.
- • Regularly checking battery voltage with a multimeter. A healthy 12V battery should read 12.6-12.8 volts when fully charged and the car is off.
Permanent fix
- Diagnose and replace faulty Data Communication Module (DCM). Part number 86259FJ020 (or equivalent revision) often applies to affected models, but always verify with VIN.
- Perform a parasitic draw test to identify the problematic circuit. This involves using a multimeter to measure current draw with the car off and systematically pulling fuses to isolate the circuit.
- Ensure all aftermarket accessories are properly wired and not causing a constant draw.
- Replace a faulty battery if it has been repeatedly deep-cycled and can no longer hold a charge effectively.
Related recalls / TSBs
FAQ
What causes battery drain / parasitic draw?
The primary culprit is often the Data Communication Module (DCM), which is integral to the Starlink telematics system. A software glitch or an internal fault within the DCM can prevent it from entering a low-power "sleep" mode, leading to a constant draw on the battery even when the ignition is off. Other less common causes include aftermarket accessories, faulty relays, or a failing alternator diode.
How much does it cost to fix?
National average $400–$1,200.
Is this a DIY repair?
Difficulty 2/5. Diagnose and replace faulty Data Communication Module (DCM). Part number 86259FJ020 (or equivalent revision) often applies to affected models, but always verify with VIN.
What are the symptoms?
Dead battery after sitting overnight or for a few days; Difficulty starting the vehicle; Battery warning light illumination (after jump start); Starlink system not functioning correctly