---
title: "Sony FDR-AX43A Battery Problem"
canonical: "https://gadgetguides.org/sony-fdr-ax43a-battery-problem/"
author: "Arian"
published: "2026-09-05T14:44:55+00:00"
modified: "2026-09-05T14:44:55+00:00"
language: "en-US"
site: "Gadget Guides"
description: "If your Sony FDRAX43A battery problem has you guessing whether it's the charger, the battery, or the camera itself, you're not alone. This camcorder is a…"
categories: "Cameras & Drones"
attribution: "Gadget Guides (https://gadgetguides.org/)"
---

# Sony FDR-AX43A Battery Problem

If your Sony FDR-AX43A battery problem has you guessing whether it's the charger, the battery, or the camera itself, you're not alone. This camcorder is a solid performer for home video and event work, but its power system can be unpredictable. The good news is that most battery issues follow predictable patterns.

 

Manufacturer specifications indicate the NP-FV70 battery delivers roughly 60 minutes of 4K recording. As of 2026, many users report shorter lifespans as batteries age, especially units stored for long periods. That's usually the first sign something needs attention.

 

Let's walk through the most common battery problems and what they actually mean.

 

## Quick Answer

 

A Sony FDR-AX43A battery problem usually has one of four causes. The battery is old and worn out. The charger is not delivering power.

 

The camera firmware is outdated. Or the battery is a third-party brand the camera rejects. Check the battery for swelling first.

 

If it's swollen, stop using it immediately. If it's flat, try a full charge cycle. If the camera still won't power on, reset the camera by removing the battery and holding the power button for 30 seconds.

 

That clears most software glitches.

 

![Sony FDR-AX43A battery problem](https://gadgetguides.org/wp-content/uploads/2026/09/sony-fdr-ax43a-battery-problem-mtohv3a2.webp)

 

Image source: Web (Bing) / tristatecamera.com (Web image (fair-use with source credit))

 

## Common Battery Problems with the Sony FDR-AX43A

 

The three most frequent complaints we see in user forums and aggregate reviews are the battery not charging at all, draining way too fast, or the camera flat-out refusing to recognize it. Each points to a different root cause.

 

**Battery won't charge.** The LED on the charger stays dark, or the camera shows "Battery exhausted" immediately after an overnight charge. This often means the battery has entered deep discharge mode. Lithium-ion cells that drop below a certain voltage threshold simply refuse to take a charge from standard chargers.

 

The NP-FV70 and NP-FV100A both use Sony's InfoLithium chip, which can shut down the cell if voltage drops too low.

 

**Battery drains too fast.** You get 15 minutes of recording instead of the expected 60. This is almost always age-related. Lithium-ion batteries lose capacity with every charge cycle.

 

After 300 to 500 cycles, the usable capacity drops significantly. Cold weather also causes temporary capacity loss. If you're shooting outdoors below 0°C, the battery may appear dead even if it's fully charged.

 

**Camera doesn't recognize the battery.** The camera powers on but shows "No battery" or "Incorrect battery" on the display. This is common with third-party replacements. The InfoLithium chip communicates with the camera via a proprietary protocol.

 

Some aftermarket brands don't implement this correctly, so the camera gets no data and assumes the battery is missing or faulty.

 

**Battery is physically swollen.** A bulging battery case is a safety hazard, not a performance issue. Stop using it immediately. Swelling means internal chemical breakdown is producing gas.

 

This is a fire risk.

 

## How the AX43A Battery System Actually Works

 

The Sony FDR-AX43A uses the InfoLithium system, which is smarter than a standard battery pack. The battery contains a small microprocessor that tracks remaining charge, voltage, and temperature. The camera reads this data and displays the remaining recording time in minutes.

 

That's why you see a live countdown instead of a vague battery icon.

 

![NP-FV70 battery InfoLithium](https://gadgetguides.org/wp-content/uploads/2026/09/np-fv70-battery-infolithium-mtohv4do.webp)

 

Image source: Web (Bing) / shop-battery.com (Web image (fair-use with source credit))

 

The AC adapter charges the battery through a dedicated DC-in port on the camera. It delivers 1.5 amps, which is the fastest method. You can also charge via USB, but the camera limits USB input to about 0.8 amps.

 

That means a USB charge takes roughly twice as long. The USB option is fine for topping off overnight, but not for quick turnaround between shoots.

 

The battery itself is a 7.2V lithium-ion cell. The standard NP-FV70 is rated at 1960 mAh. The larger NP-FV100A doubles that to 3920 mAh.

 

Both fit the same compartment, but the FV100A is physically taller and heavier. The camera's battery management system monitors voltage and temperature to prevent overcharging. If the battery gets too hot during charging, the system cuts off power until it cools down.

 

One detail that trips people up: the InfoLithium chip maintains a memory of the battery's charge history. If you store a battery fully discharged for months, the chip may lose track of the real cell voltage. The camera then shows an incorrect percentage.

 

This is why a full discharge-recharge cycle can sometimes fix a battery that seems to drain fast. It recalibrates the chip to the real cell condition.

 

This same system is used in other Sony professional camcorders. If you've worked with [Sony's HXR-NX80 troubleshooting](https://gadgetguides.org/sony-hxr-nx80-troubleshooting/) before, you'll notice the same battery logic applies. The communication protocol between battery and camera is identical across the lineup.

 

## The Decision Tree – Diagnose Your Exact Battery Issue

 

Here's the practical part. Stop guessing and start testing. Follow the branch that matches your symptom.

 

### Branch 1: Battery Won't Charge

 

**Check the charger first.** Plug the AC adapter into the camera and turn the camera on. If the camera powers on, the charger is working. If not, test the adapter with a different device if possible.

 

The adapter is a common failure point, especially if the cable gets bent at the connector.

 

**If the charger works, test the battery.** Connect the battery directly to an external charger if you have one. The Sony BC-TRV wall charger is faster and more reliable than in-camera charging. If the external charger recognizes the battery and starts charging, the camera's charging circuit may be faulty.

 

This is a known issue on some AX43A units. You can still use the camera. You just need to charge batteries externally.

 

**If the battery still won't charge, it's likely in deep discharge.** Some third-party chargers include a "recovery" mode that applies a low current to bring the voltage back up. Sony's official charger does not offer this. If the battery is a genuine Sony unit that's less than two years old, it may be covered under warranty.

 

Third-party batteries are usually cheaper to replace than recover.

 

### Branch 2: Battery Drains Too Fast

 

**Check the recording settings.** 4K recording at 60 fps draws more power than 1080p at 30 fps. The LCD screen brightness also affects battery life. If you've cranked the screen to maximum brightness, expect 20 to 30 percent less runtime.

 

**If settings are normal, the battery is likely aged.** Count the approximate charge cycles. If you've charged the battery more than 300 times, its capacity is probably below 80 percent of the original spec. The NP-FV70 is rated for about 300 cycles before noticeable degradation.

 

The NP-FV100A tends to last longer because it has more cells sharing the load.

 

**Test with a known good battery.** Borrow a friend's NP-FV70 or buy a fresh one. If the new battery gives normal runtime, the old battery is the problem. If both batteries drain fast, the camera has a power draw issue.

 

This could be a stuck component on the main board, which requires professional repair.

 

### Branch 3: Battery Not Recognized by Camera

 

**This is almost always a third-party battery issue.** The camera's InfoLithium system is proprietary. Sony licensed it to a few third-party manufacturers, but many budget brands skip the licensing. The camera sees no communication from the chip and assumes the battery is absent or invalid.

 

**Check the battery contacts.** Dirty terminals can interrupt the data signal. Clean them with a dry cotton swab and isopropyl alcohol. Let them dry completely before inserting the battery.

 

This fixes about one in ten recognition issues.

 

**Update the camera firmware.** Sony occasionally releases firmware updates that improve battery compatibility. As of 2026, the latest firmware for the FDR-AX43A is version 2.01. You can check your current version in the camera menu under Setup.

 

If you're behind, update via Sony's support site. This has resolved recognition issues for some users running older firmware. If you've faced similar issues with other gear, the [Sony PXW-Z90V troubleshooting](https://gadgetguides.org/sony-pxw-z90v-troubleshooting/) guide covers firmware update steps that apply here too.

 

### Branch 4: Physical Damage or Swelling

 

**Stop using the battery immediately.** A swollen lithium-ion battery can rupture, catch fire, or leak toxic electrolyte. Do not try to charge it. Do not puncture it.

 

Place it in a fireproof container if possible.

 

![swollen battery Sony camcorder](https://gadgetguides.org/wp-content/uploads/2026/09/swollen-battery-sony-camcorder-mtohv51a.webp)

 

Image source: Web (Bing) / shoptheworld.in (Web image (fair-use with source credit))

 

**Dispose of it properly.** Lithium-ion batteries are hazardous waste. Most electronics retailers and municipal recycling centers accept them. Do not throw it in the trash.

 

The [US EPA](https://www.epa.gov) regulates battery disposal as hazardous waste. Check your local guidelines for specific drop-off locations.

 

**Replace the battery.** A swollen battery is not repairable. Buy a new one. If you're replacing a genuine Sony battery, stick with an official Sony unit.

 

The cost difference is small relative to the risk of a fire. If you're on a tight budget, look for third-party batteries that explicitly state compatibility with Sony InfoLithium systems. Avoid unbranded no-name packs.

 

## Common Mistakes to Avoid When Troubleshooting

 

**Mistake one: assuming the battery is dead without testing the charger.** The AC adapter is the most common failure point, not the battery. Always test the charger first. Plug it into the camera and see if the camera powers on.

 

If it does, the charger is working. If not, try a different outlet or a different adapter.

 

**Mistake two: storing the battery fully discharged for months.** Lithium-ion batteries self-discharge over time. If you leave a battery at 0 percent for three months, the voltage can drop below the safe threshold. The internal protection circuit then shuts down the battery permanently.

 

Store batteries at about 40 to 60 percent charge for long-term storage. This is the standard recommendation from all major battery manufacturers, per [Battery University](https://batteryuniversity.com) research.

 

**Mistake three: using a USB charger that's too weak.** The camera needs at least 5V and 2A to charge via USB. Many phone chargers output only 1A or 1.5A. The camera will accept the charge but it will be extremely slow.

 

You might think the battery is not charging when it's actually trickle charging at a rate that takes 12 hours. Use the AC adapter or a dedicated external charger for reliable charging.

 

**Mistake four: mixing old and new batteries in the same bag.** Different batteries at different charge levels can short-circuit each other if the terminals touch. Keep battery terminals covered. Use the plastic terminal caps that come with new batteries.

 

If you lost them, a piece of electrical tape works fine.

 

**Mistake five: ignoring firmware updates.** Camera firmware controls battery management logic. Sony releases updates that fix charging bugs and improve compatibility with newer batteries. If you're running firmware from 2020, you might be missing fixes that solve your exact issue.

 

Check for updates. This is a free fix that takes 10 minutes. Many users dismiss it because they assume the problem is hardware.

 

For broader camera issues, the [Sony FDR-AX43A not recording](https://gadgetguides.org/sony-fdr-ax43a-not-recording/) guide covers other firmware-related glitches you might encounter.

 

## Long-Term Battery Care and Optimization

 

**Charge correctly.** Avoid charging to 100 percent every time if you don't need the full runtime. Lithium-ion batteries last longest when kept between 20 and 80 percent charge. This is backed by lithium-ion chemistry research.

 

If you're only shooting for 30 minutes, charge to 80 percent. If you need the full battery, charge to 100 percent. The difference in cycle life can be significant.

 

**Avoid extreme temperatures.** The operating range for the NP-FV70 and NP-FV100A is 0°C to 40°C. Charging below 5°C can damage the battery. The camera's charging circuit should prevent this, but don't test it.

 

If you're shooting in cold weather, keep spare batteries in an inside pocket where your body heat keeps them warm. Swap them in only when needed. The cold battery will appear dead until it warms up.

 

**Use the right charger.** The Sony AC adapter is optimized for the InfoLithium system. It communicates with the battery's chip to determine the optimal charging current. Third-party chargers may not have this communication.

 

They apply a fixed current, which can be too high or too low. If you use a third-party charger, look for one that explicitly supports InfoLithium charging profiles.

 

**Rotate your batteries.** If you have multiple batteries, label them with the purchase date. Use them in rotation. This prevents one battery from getting 500 cycles while another sits unused for a year.

 

An unused battery can degrade just as fast as an overused one, especially if stored at high charge.

 

**Calibrate occasionally.** If you notice the battery percentage jumping from 30 percent to 0 percent suddenly, the InfoLithium chip needs recalibration. Run a full discharge cycle. Record until the camera shuts off.

 

Then charge to 100 percent without interruption. This resets the chip's capacity estimate. Do this every 20 to 30 cycles if you see erratic behavior.

 

This same calibration approach applies to other Sony camcorders, which you can explore in the [Sony FDR-AX53 autofocus problems](https://gadgetguides.org/sony-fdr-ax53-autofocus-problems/) guide for related camera maintenance tips.

 

**Know when to replace.** A battery that delivers less than 50 percent of its original runtime is effectively dead. It's not going to improve. The capacity loss is permanent.

 

Replace it. The NP-FV70 is a mature product, and replacement costs are reasonable. Don't keep using a degraded battery that leaves you stranded mid-shoot.

 

## When to Replace vs. When to Repair

 

**Replace the battery if it's swollen, over three years old, or delivers less than half its original runtime.** Swelling is non-negotiable. A bulging battery is a fire hazard. Replace it immediately.

 

Age-related capacity loss is also permanent. Lithium-ion cells degrade chemically. No repair can reverse that.

 

**Repair is only worth considering for the camera itself, not the battery.** If the camera's charging circuit fails, a repair shop can replace the DC-in board or the internal charging components. This costs roughly $80 to $150 depending on the shop. Compare that to a new battery at $40 to $60.

 

If the camera is under warranty, send it to Sony for free.

 

**When the battery contacts are dirty, that's a cleaning job, not a repair.** Use isopropyl alcohol and a cotton swab. Clean both the battery terminals and the camera's contact pins. Let everything dry for 10 minutes.

 

This fixes intermittent connection issues without any cost.

 

**When the battery won't charge but the camera works fine, test with an external charger.** If the battery charges on an external charger, the camera's charging circuit is the problem. You can keep using the camera. Just charge batteries externally.

 

That's a workaround, not a repair. It costs nothing.

 

**When the camera firmware is outdated, that's a free fix.** Update via Sony's support site. This resolves battery recognition issues and charging bugs. It takes 10 minutes with a memory card and a computer.

 

No replacement needed.

 

**When the battery is a third-party brand and the camera doesn't recognize it, replacement is the only fix.** No firmware update will add compatibility for an unlicensed chip. Buy a genuine Sony battery or a brand that explicitly states InfoLithium compatibility. This is the most common scenario we see in troubleshooting guides for similar camcorders, and the same logic applies across the lineup.

 

## Frequently Asked Questions

 

### How do I reset the battery on my Sony FDR-AX43A?

 

Remove the battery from the camera. Press and hold the camera's power button for 30 seconds. This drains any residual charge from the internal capacitors.

 

Reinsert the battery and turn the camera on. The system resets and clears minor software glitches.

 

### Can I use a higher capacity battery like the NP-FV100A?

 

Yes. The NP-FV100A is fully compatible with the FDR-AX43A. It fits the same compartment and delivers roughly double the recording time.

 

The camera automatically recognizes the higher capacity and adjusts the remaining time display. The battery is physically larger and heavier.

 

### Why does my Sony battery drain so fast in cold weather?

 

Lithium-ion batteries lose capacity temporarily in cold temperatures. Below 0°C, the chemical reactions inside the battery slow down. The camera reads this as a low charge.

 

The battery recovers its full capacity once it warms up. Keep spare batteries in an inside pocket.

 

### Is it safe to leave the battery charging overnight?

 

The camera's charging circuit stops charging once the battery reaches full capacity. The InfoLithium system prevents overcharging. However, leaving any lithium-ion battery unattended for long periods carries a small risk.

 

It's better to charge during the day when you can monitor it.

 

### How do I know if my battery is counterfeit?

 

Genuine Sony batteries have a holographic label, a printed serial number, and consistent build quality. Counterfeit batteries often have misspelled text, loosely fitting plastic shells, and no hologram. The camera may also show "Incorrect battery" or fail to display the remaining time in minutes.

 

Buy from authorized dealers.

 

### What should I do with a swollen battery?

 

Stop using it immediately. Do not charge it. Do not puncture it.

 

Place it in a fireproof container if possible. Take it to a battery recycling center or an electronics retailer that accepts hazardous waste. Do not throw it in the trash.

 

Check local regulations for proper disposal.