2010 Subaru Legacy Battery Replacement (Car)
Complete guide to 2010 Subaru Legacy battery replacement (car). Cost estimates, difficulty level, time required, and environmental impact.
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💰 Cost Breakdown
💡 Tip: Costs vary by location and repair shop. Authorized service centers typically charge more than independent repair shops.
🔧 Repair Overview
Battery Replacement (Car) is one of the most common repairs for 2010 Subaru Legacy. This repair involves replacing the damaged electrical component with a new or refurbished part. The process typically takes 30 min and requires easy skill level.
What You'll Need
- Replacement electrical part (OEM or aftermarket)
- Precision screwdriver set (Phillips #000 or pentalobe)
- Opening tools (plastic spudger, suction cup)
- Adhesive strips or glue
- Clean workspace with good lighting
Step-by-Step Process
Step 1:
These are the [stock] horns you are looking for. One is located on the left-side of the radiator (when looking at the car), while the other one is next to the air intake / water tank.
Both horns are identical in terms of disassembly/replacement. The one mounted near the radiator is a bit harder to access, since the hex bolt is obscured by a frame -- but it's not that much more difficult to remove.
Step 2:
Use a 12 mm wrench to remove the bolt holding the horn in place.
Step 3:
Unplug the power connector from the horn, and use a wire stripper to expose a bare portion of the wire. The "20 ga" hole seemed the best fit for this purpose.
The PIAA horns have their power/ground connections on top of the horn, so the stock wire won't be long enough. At the same time, the ground cables that come with the horns are too long -- which is a perfect hack in this case!
Snip about 4" of the ground cable wire (the 1/4" female spade connector side) and use a butt connector to attach it to the horn's power wire.
It may be a good idea to insulate the connection with some electrical tape after it's been crimped properly.
Step 4:
Now you should have a shortened ground cable with a bare wire on one end, and that half-loop connector on the other.
Attach another 1/4" female spade connector to the end of the ground cable, and plug it into the ''lower'' of the two male spade connectors on the PIAA horn.
Step 5:
The factory bolt is a bit larger in diameter than the half-circle connector will allow -- unless it is expanded! So insert a needle-nose plier into the center for the connector and then spread it apart in order to accommodate the bolt.
Route the bolt through the horn's mounting hole.
Screw the bolt / ground wire / horn assembly into the factory mounting hole.
Step 6:
Plug in the DC power line into the top male connector of the horn. The final wiring / horn assembly can be seen in the first image.
Once you're done with the first horn, the second should be the same exact procedure -- so go get 'em!
Step 7:
So that's it! Here's a before-and-after horn comparison, so you get an idea of the sound difference.
I don't believe the PIAAs are that much more loud, but they are definitely a nicer sounding setup than the stock honkers.
📖 Repair guide provided by iFixit - The free repair manual. Licensed under CC BY-NC-SA 3.0.
iFixit Difficulty: Moderate | Time: NaNh NaNm
DIY vs Professional Repair
✋ DIY Repair
- ✅ Lower cost (parts only: $60-$120)
- ✅ Learn new skills
- ❌ Risk of further damage
- ❌ No warranty
- ❌ Requires tools and time
🔧 Professional Repair
- ✅ Expert installation
- ✅ Warranty included
- ✅ Faster turnaround
- ❌ Higher cost ($100-$200)
- ❌ Need to find reputable shop
Environmental Impact
By choosing to repair your 2010 Subaru Legacy instead of replacing it, you're preventing approximately 5785 kg of CO₂ emissions. Manufacturing a new 2010 Subaru Legacy generates 5800 kg of CO₂, while this repair only produces about 15 kg of CO₂. That's a 100% reduction in carbon emissions!
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