The Highlander from 2003 uses a standard 12-volt automotive battery, and the most common replacement size is Group Size 24F.
In more detail, the 2003 Highlander (first generation) relies on a conventional 12-volt lead-acid battery to power the starter and electrical system. While 24F is the typical replacement size for many configurations, exact specifications can vary by engine type (2.4L or 3.0L) and regional market. Always verify the exact group size, CCA, and date code on your current battery or in the owner's manual before purchasing a replacement.
Recommended battery specifications
The following specs guide most 2003 Highlander replacements. They reflect common factory settings and typical aftermarket equivalents. Always double-check the label on your current battery or the owner's manual for your exact model.
- Group size: 24F (the most commonly used size for 2003 Highlanders).
- Type: Flooded lead-acid automotive battery (non-AGM in standard trims; AGM may be available as an upgrade in some markets).
- Voltage: 12 volts.
- Cold-cranking amps (CCA): roughly 650–800 CCA, depending on climate and engine variant.
- Amp-hour rating (Ah): commonly around 60–70 Ah for typical configurations.
When selecting a battery, ensure it fits the battery tray, has matching terminal configuration, and includes the proper hold-down hardware. If in doubt, a parts retailer can verify compatibility using your VIN.
How to verify the exact battery for your vehicle
Because small variations exist by engine and market, use these checks to confirm you’re buying the right battery.
Check the existing battery label
Read the group size, CCA, and date code on the top or label of the current battery to match the replacement exactly.
Consult the owner's manual or a parts professional
The manual lists the recommended group size and specifications, and a professional can pull the right battery using your VIN.
In most cases, a standard 12V, 24F-group automotive battery will be the correct replacement for a 2003 Toyota Highlander, but always verify due to possible engine and market variations.
Summary
For a 2003 Toyota Highlander, expect a 12-volt, conventional flooded lead-acid battery, with Group Size 24F being the common replacement. Confirm exact specs on your current battery or in the owner’s manual, especially if you have a 2.4L four-cylinder or 3.0L V6 engine. Upgrading to a battery with higher CCA or Ah can be beneficial in very cold climates, but ensure fitment and terminal configuration match.