Quick answer: Battery Replacement on a 1991–1995 Toyota MR2 is rated Easy and takes about 30-90 minutes. You'll need 2 tools for this job, and parts cost about $180. This guide walks you through the full job step by step, including the mistakes to avoid.
| Part Name |
Part Number |
Price |
Buy |
| Replacement 12-volt battery for 1991-1995 Toyota MR2; verify group size, CCA, terminal layout, and VIN fitment |
— |
$180.00 |
|
| Anti-corrosion terminal protectant or felt washers (optional) Optional |
— |
$8.00 |
|
About prices: shown prices are typical retail averages and change frequently; cheaper alternatives may be available. Confirm the current price before buying.
💡 Pro tip: Order all parts at once to save on shipping
Step-by-Step Instructions
Follow these steps carefully
1
Know where the MR2 battery actually is
The 1991-1995 MR2 (SW20) is mid-engined — its battery is in the FRONT trunk (frunk), behind the spare tire, NOT the engine bay. Buy BCI Group 24F, SAE top posts, positive terminal top right. Fault signs: slow crank, dim lights, resting voltage under 12.4 volts.
🔧 Mechanic's note — Tom Becker
I can't tell you how many MR2 owners I've watched pop the rear engine lid looking for this battery. Open the front hood — it's behind the spare tire, and that's the first thing to know about this car.
2
Open the frunk and make it safe
Park level, brake set, ignition off, key out. Open the front hood and pull the spare tire to expose the tray. Safety glasses and gloves; note your radio presets. Tools: 10 mm wrench, wire brush, terminal protector.
3
Disconnect the battery, negative first
Negative (black) clamp off with the 10 mm wrench; tuck the cable toward the frunk wall. Then the positive (red). Tight around the spare-tire well — never bridge the posts with the wrench; a 24F holds enough energy to weld it.
4
Unbolt the hold-down and lift out the battery
Remove the hold-down or J-bolts; lift the old 24F straight up (~42 lbs, awkward). Scrub any acid corrosion from the tray with baking-soda solution. Drop the new 24F in, terminals matching the cables, bolt the hold-down tight.
5
Reconnect, start, and check the charging system
Positive first, then negative; snug both so they can't twist. Reinstall the spare tire and close the frunk. Start the engine: brisk crank, no battery light. Running voltage at the posts: 13.5-14.5 volts. Recycle the old battery at the store.
All Done!
Test your repair before closing everything up. If something doesn't work right, double-check your steps.
⚠️ Common Mistakes to Avoid
- • Buying by appearance instead of group size, CCA, polarity, and hold-down fit
- • Shorting the positive terminal to the body with a metal tool
- • Lifting the battery by damaged terminals or leaving it unsecured
- • Skipping battery registration, window/clock resets, or charging-system checks when required
- • Assuming a new battery fixes a parasitic draw or charging fault
