The 2020 Subaru Ascent uses a standard 12-volt automotive battery. The exact group size and whether the battery is a conventional flooded lead-acid unit or an AGM (absorbed glass mat) battery depend on the vehicle’s equipment, notably whether it has Idle Start Stop (ISG).
In practice, you should verify the specifications on your current battery label or in the owner's manual, or confirm with a Subaru dealer using your VIN. Replacements should match the original group size and type to ensure proper fit, charging, and reliability. Below is a guide to what to look for and how to replace or verify the battery.
Key specifications to confirm
To buy the correct replacement, you need to check these common specs on the battery or in the vehicle documentation. The exact numbers can vary by market and trim, so use the original battery as the primary reference.
- Group size: the physical size and terminal layout. Subarus often use a Group Size around 35 or similar for many trims, but the exact size should be confirmed from the current battery label or official documentation.
- Voltage: 12 volts for the starting and electrical system.
- Type: mostly conventional flooded lead-acid; some ISG-equipped configurations may require an AGM battery for better performance and durability.
- Cold Cranking Amps (CCA): a figure that varies by group size and climate; typical replacements fall in the 500–650 CCA range, but check the label for your exact requirement.
- Reserve Capacity (RC): approximate duration the battery can sustain a standard load; commonly around 100–120 minutes depending on the group size.
- Battery date code: helps determine remaining useful life; most automotive batteries are expected to perform well for about 3–5 years under normal conditions.
Conclusion after list: Because there are variations by market and equipment, always verify the exact group size, CCA, RC, and type from the original battery or official Subaru sources before purchasing a replacement.
How to verify and replace
These steps help ensure you install the correct battery and complete the replacement safely.
- Check the current battery label for group size, CCA, RC, and whether it is conventional or AGM.
- Consult the owner's manual or a Subaru dealer with your VIN to confirm the exact OEM specification for your trim and region.
- Consider an AGM replacement if your Ascent has Idle Start Stop or if you operate in extreme temperatures or expect frequent starts and stops.
- When replacing, use the same group size and compatible terminal orientation; ensure proper polarity, clean terminals, and secure mounting.
- Recycle the old battery at an authorized facility; many retailers will accept and recycle it.
Conclusion: After replacement, verify the charging system and battery management system are functioning correctly and reset electronics as needed per Subaru guidelines.
Notes on maintenance and care
To maximize battery life, keep terminals clean and tight, avoid deep discharges, and monitor charging performance, especially in extreme weather. If voltage drops under load, have the charging system tested promptly.
Summary
The 2020 Subaru Ascent relies on a 12-volt automotive battery whose exact group size and type depend on equipment such as Idle Start Stop. Always verify the specific group size, CCA, RC, and whether your vehicle uses a conventional or AGM battery from the original battery label, the owner's manual, or a Subaru dealer using your VIN. Using OEM-recommended specifications and proper disposal practices helps ensure reliable starts and long-term reliability.