🔧 NX - 12V Battery Replacement

Your NX’s 12V battery powers starting and all the electronics (locks, lights, computers). Replacing it is straightforward, but the order you disconnect/reconnect the cables matters to prevent sparks and electrical damage.

Difficulty Level: Beginner | Estimated Time: 0.5-1.0 hours

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⚠️ Safety & Precautions

• ⚠️ Keep the ignition OFF and the key fob at least 10 feet away.
• ⚠️ Wear safety glasses and gloves—battery acid is corrosive.
• ⚠️ Disconnect the negative (-) terminal first to reduce short-circuit risk.
• ⚠️ Do not let a tool touch the battery positive (+) and any metal body part at the same time.
• ⚠️ No battery disconnect is required for this job, but you will lose some settings (clock, windows auto-up) if you don’t use a memory saver.

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🔧 Required Tools

You'll need the following tools for this repair:

• Safety glasses
• Nitrile gloves
• 10mm combination wrench
• 10mm socket
• 3/8" ratchet
• 6" socket extension
• Torque wrench (5-30 Nm range)
• Battery terminal brush
• Trim/panel tool
• Fender cover
• 12V memory saver (specialty)

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• 12V battery (BCI Group H5/47) - Qty: 1
• Battery terminal anti-corrosion felt pads - Qty: 2
• Battery terminal protectant spray - Qty: 1
• Dielectric grease - Qty: 1

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📋 Before You Begin

• 🔹 Park on level ground, shift to Park, and set the parking brake.
• 🔹 Open the hood and install a fender cover (a protective mat) to avoid paint scratches.
• 🔹 Optional: connect a 12V memory saver (a small backup power supply) to keep settings. Follow the memory saver’s instructions exactly.
• 🔹 If you’re not using a memory saver, note that you may need to re-initialize the power windows after.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Access the battery

• Open the hood and locate the 12V battery in the engine bay.
• If there’s a plastic cover/duct in the way, remove it using a trim/panel tool.

Step 2: Disconnect the negative (-) battery cable

• Use a 10mm wrench to loosen the nut on the negative (-) terminal clamp.
• Wiggle and lift the clamp off the battery post, then move it aside so it can’t spring back.
• Negative off first prevents accidental shorting.

Step 3: Disconnect the positive (+) battery cable

• Use a 10mm wrench to loosen the nut on the positive (+) terminal clamp.
• Lift the clamp off and move it aside.
• If your NX has a positive terminal cover, fold it back into place to reduce accidental contact.

Step 4: Remove the battery hold-down

• Use a 10mm socket, 3/8" ratchet, and 6" socket extension to remove the battery hold-down hardware.
• Lift the hold-down bracket off and set it aside.

Step 5: Remove the old battery

• Lift the battery straight up and out. Batteries are heavy—use both hands.
• If there is a battery vent tube attached, carefully pull it off before lifting the battery fully out.

Step 6: Clean the terminals and tray

• Use a battery terminal brush to clean the inside of both cable clamps until the metal is bright.
• Wipe the battery tray clean and ensure nothing is loose under the new battery.

Step 7: Install the new battery

• Place the new battery into the tray in the same orientation as the old one (positive and negative posts match the cables).
• Reconnect the vent tube if equipped.

Step 8: Reinstall and tighten the hold-down

• Reinstall the hold-down bracket using the 10mm socket, ratchet, and extension.
• Use a torque wrench to tighten the hold-down fasteners: Torque to 20 Nm (15 ft-lbs).

Step 9: Reconnect the positive (+) terminal first

• Install the positive clamp onto the battery post.
• Use a torque wrench with a 10mm socket to tighten: Torque to 5.4 Nm (48 in-lbs).
• Apply a light coat of dielectric grease around (not between) the connection, then install the terminal cover.

Step 10: Reconnect the negative (-) terminal

• Install the negative clamp onto the battery post.
• Use a torque wrench with a 10mm socket to tighten: Torque to 5.4 Nm (48 in-lbs).
• Spray battery terminal protectant on both terminals to reduce corrosion.

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✅ After Repair

• 🔹 Start the NX and confirm it cranks normally and the interior/exterior lights are steady.
• 🔹 Check that the battery is secure (no movement) and that both clamps are tight.
• 🔹 Reset the clock and any saved settings if they were lost.
• 🔹 Power window auto function reset (if needed): with the engine on, fully lower the window, then fully raise and keep holding the switch for 2-3 seconds.
• 🔹 If warning lights remain after a short drive, recheck terminal tightness and cleanliness.

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💰 DIY vs Shop Cost

Shop Cost: $250-$450 (parts + labor)

DIY Cost: $180-$300 (parts only)

You Save: $70-$150 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 0.5-1.0 hours.

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🎯 Ready to get started?

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