---
title: "au (KDDI) slow internet in Japan: tests, evidence and complaints · Kilobat Guides"
url: "https://kilobat.app/guides/au-hikari-hgw-slow-internet-complaint"
description: "au (KDDI) internet slow or dropping out in Japan? Check equipment, compare tests, keep evidence and follow the complaint route."
---

# au (KDDI) slow internet in Japan: tests, evidence and complaints

If your au (KDDI) connection is slow or unreliable, start with these equipment checks. Then document a repeatable result and ask for a specific investigation.

Applies to: Paths checked in NEC Platforms’ BL3000HM 機能詳細ガイド (feature guide), linked from the BL3000HM manual, and on au.com. The BL1500HM uses the same address and login; its guide puts UPnP directly under **ネットワーク設定 › UPnP設定**. · Checked: 3 November 2026

## When this helps

- You use au (KDDI) in Japan.
- Your connection is slower than expected, drops out or performs badly at certain times.

## Check your auひかり ホームゲートウェイ

These checks apply to auひかり ホームゲートウェイ. Check the model before following its menus.

1. Open **基本情報** (Basic info) for the lights, firmware, WAN address, DNS servers and Wi-Fi channels in use.
2. Open **ネットワーク診断 › ログの表示** (Show log) for the device log; **ファイルへ保存** (Save to file) downloads it.
3. **ホームゲートウェイ詳細設定 › 4.メンテナンス › PINGテスト** (Ping test) checks whether an address answers from the gateway.

## Separate the service from your home Wi-Fi

For the exact settings and supported equipment, see [the auひかり ホームゲートウェイ guide](https://kilobat.app/routers/au-hikari-hgw).

Do not factory-reset the equipment as a first step. A reset can erase service settings and interrupt phone service.

1. Compare a wired connection to the router with Wi-Fi on the same device.
2. Repeat the same test server during the slowdown and at a quieter time.
3. Record download, upload, latency and whether another household device was using the connection.

## How to complain to au (KDDI)

Use [au (KDDI)’s official support](https://www.au.com/support/service/internet/guide/service/quickweb_bl3000/) to report the fault. Request a formal complaint reference if it remains unresolved.

Include the plan wording, dates, test conditions, previous references and the specific outcome you want. Ask for a written response.

Check the complaints procedure in your Japan service contract before escalating. Use the national regulator’s consumer guidance for your service.

## Collect the evidence with Kilobat

On a Mac, Kilobat can record connection checks and produce a support report. Review the report and add your test conditions before sharing.

The basic report export is free. [Kilobat Pro’s complaint wizard](https://kilobat.app/internet-complaint) helps assemble your evidence, impact and requested resolution into a draft you review and send.

Measurements cover this Mac while monitoring ran. They cannot prove whole-home uptime, establish provider fault or replace a required official measurement procedure.

## Sources

- [au: クイック設定Web（BL3000HMをご利用の方）](https://www.au.com/support/service/internet/guide/service/quickweb_bl3000/)
- [au: BL3000HM ファームウェア情報 (firmware updates)](https://www.au.com/support/service/internet/guide/modem/bl3000hm/firmware/)
- [au: Aterm BL3000HM 取扱説明書 (manual, PDF)](https://www.au.com/content/dam/au-com/support/internet/guide/modem/bl3000hm/pdf/bl3000hm_manual.pdf)
- [au: auひかり ホーム 新ホームゲートウェイのご提供開始について (2022)](https://www.au.com/information/notice_internet/service/20220921-01/)
- [NEC Platforms: BL3000HM 機能詳細ガイド, ホームゲートウェイ詳細設定](https://www.aterm.jp/function/bl3000hm/guide/web_hgw_setting.html)
- [NEC Platforms: BL3000HM 機能詳細ガイド, 再起動](https://www.aterm.jp/function/bl3000hm/guide/web_reboot.html)
- [NEC Platforms: BL3000HM 機能詳細ガイド, その他の設定 (UPnP)](https://www.aterm.jp/function/bl3000hm/guide/web_others.html)
- [NEC Platforms: BL3000HM 機能詳細ガイド, 基本情報](https://www.aterm.jp/function/bl3000hm/guide/web_status.html)
- [NEC Platforms: BL3000HM 機能詳細ガイド, 接続状態表示](https://www.aterm.jp/function/bl3000hm/guide/web_network_map.html)
- [NEC Platforms: BL3000HM 機能詳細ガイド, 無線LAN詳細設定(5GHz)](https://www.aterm.jp/function/bl3000hm/guide/web_wlan5g.html)
- [NEC Platforms: BL3000HM 機能詳細ガイド, メッシュ中継機を接続する](https://www.aterm.jp/function/bl3000hm/guide/wlan_connect_meshrep.html)
- [NEC Platforms: BL3000HM 機能詳細ガイド, セカンダリSSIDに接続する](https://www.aterm.jp/function/bl3000hm/guide/wlan_connect_2ndssid.html)
- [KDDI: BL1500HM 機能詳細ガイド, UPnP設定](https://kddi-tech.com/hgw-bl1500hm/contents/settings_L4_14.html)

Checked on 3 November 2026.

## Related guides

- [Internet slower than advertised? Test it before you complain](https://kilobat.app/guides/internet-slower-than-advertised): A low speed test is a starting point.
- [Wi-Fi slow but Ethernet fast? Find the wireless bottleneck](https://kilobat.app/guides/wifi-slow-ethernet-fast): If the same device is consistently faster on Ethernet, investigate the wireless path first.
- [Slow internet complaint letter: a template with the evidence to attach](https://kilobat.app/guides/broadband-complaint-letter): A useful complaint says what happened, how you tested it and what you want the provider to do next.