Why wont my Subaru open the trunk beeps three times?
When your Subaru beeps three times as you try to open the trunk, it’s usually a warning from the trunk release or security system rather than a simple mechanical snag. The most common causes include the trunk not being fully closed, a weak key fob battery, or a fault in the latch or sensor. If the trunk won’t open, start with basic checks and then move to more detailed diagnostics or dealer assistance if needed.
What the three beeps typically mean
In many Subaru models, the number of chimes or horn beeps tied to a trunk or security event signals a condition detected by the system. Three beeps often indicate a trunk-related issue or an alert from the central locking/security system. Because exact codes can vary by model year and trim, consult your owner’s manual for model-specific meanings. The following list covers common scenarios you may encounter.
- Trunk is not fully closed or the latch is misaligned, triggering a warning.
- A sensor or the latch mechanism inside the hatch is sticking, jammed, or dirty.
- Key fob battery is weak or there is interference affecting the remote’s signal.
- Security/anti-theft system is triggered or a door is detected as ajar.
- A fuse or wiring issue affecting the trunk release or central locking circuit.
- Environmental factors (extreme cold/dirt) causing a temporary latch fault.
- Aftermarket alarms or remote-start systems interfering with normal operation.
These are common possibilities, but the exact cause can depend on your specific Subaru model and year. If the problem persists after basic checks, more in-depth diagnostics may be needed.
Diagnostic steps you can take at home
To determine the cause of the three-beep warning and gain access to the trunk, try these steps in order from simplest to more involved.
- Ensure every door and the trunk itself are fully closed. Attempt to close the trunk with the latch while gently pulling on the hatch to feel for any binding.
- Try all opening methods: the key fob button, the interior trunk release, and, if your model has one, the mechanical key on the trunk or driver’s door. If one method works and another doesn’t, the problem is likely with a switch or sensor.
- Check the key fob battery. Replace it with a fresh battery (usually CR2032) and re-test. A weak fob can cause the system to misread a request to release the trunk.
- Inspect the latch area for obstruction, corrosion, or obvious damage. Clean any dirt or debris from the latch and ensure the strike plate aligns properly.
- Inspect the relevant fuses. The trunk release and central locking circuits are often on a dedicated fuse or shared with other actuators. If you find a blown fuse, replace it with the correct rating and test again.
- Consider the security/immobilizer status. If the alarm is armed or a fault is detected, the trunk release may be inhibited. Attempt to unlock and disarm the system with the fob and ensure doors unlock normally.
- Reset the electrical system if permissible for your model. This can be as simple as turning the ignition off and back on, or temporarily disconnecting and reconnecting the battery (when safe and allowed by the owner’s manual). Note that some modern Subarus store memory settings that can be reset by battery work, so consult the manual first.
- If accessible, attempt to use the emergency trunk release inside the cargo area. If the hatch is partially open, you may be able to reach the lever or glow-in-the-dark handle and open the trunk manually.
These steps cover the most common home diagnostics. If none resolve the issue, professional evaluation is recommended to avoid damaging the latch or the electrical system.
When to seek professional help
If the trunk still won’t open or the three-beep warning persists after performing the above checks, consider contacting Subaru Roadside Assistance or visiting a dealership. A technician can verify whether the issue is a faulty latch, a wiring harness problem in the tailgate, a bad sensor, or a software/ECU fault that requires updates or reprogramming.
- The beeps continue even after replacing the key fob battery or resetting the system.
- The trunk remains jammed or only opens with an external manual method (and not via the fob or interior switch).
- You notice other electrical symptoms, such as other central locking functions acting erratically or warning lights on the dash.
- Your vehicle is under warranty or has any related service bulletins addressing trunk latch or security system behavior.
Professional inspection can diagnose hidden wiring faults, latch motor issues, or a software fault that a dealer can address with service bulletins or software updates.
Prevention and maintenance tips
Regular upkeep can reduce the likelihood of trunk beeping problems. Keep the latch and strike clean, replace the key fob battery at the recommended intervals, and ensure the trunk area is free of debris that could obstruct closure. If you notice warning beeps becoming more frequent or changing in pattern, have the system checked early to prevent a no-start or a stuck trunk scenario.
Summary
Three beeps from a Subaru when attempting to open the trunk usually signal a trunk- or security-system issue rather than a simple release failure. Start with basic checks—confirm all doors and the trunk are closed, test all opening methods, and replace the key fob battery. Inspect the latch and fuses, and reset the system if appropriate for your model. If the trunk remains unopenable or the beeps persist, seek professional help to diagnose latch or wiring faults or to update software under warranty or service bulletins. Regular maintenance can help prevent these warnings from reappearing.
