Speed Warning Chime
A speed alert that plays a repeating chime when you exceed a set speed. It recreates the "kinkon" warning buzzer once mandatory in Japanese cars. No subscription required — available to all users.
1.Overview
From the 1970s until around 2000, Japanese passenger cars were required to sound a "kinkon" chime when exceeding 105 km/h. The Speed Warning Chime recreates this iconic sound digitally.
The chime starts when you pass your chosen threshold and stops automatically when you slow down. The default is 105 km/h, but you can set it anywhere from 60 to 180 km/h — useful for speed-limit compliance, track alerts, or simply reliving the retro JDM experience.
| Chime sound | Kinkon chime (AE86 sound) |
| Repeat interval | 1.2 seconds |
| Speed source | ECU vehicle speed / falls back to GPS speed during playback |
| Default threshold | 105 km/h |
| Default state | Disabled (must be enabled manually) |
| Subscription | Not required (free for all users) |
2.Setup
Enable the chime and adjust the threshold in Settings > Speed Warning Chime.
Enabling the chime
Turn on the "Enable chime" toggle. It's off by default, so you'll need to switch it on manually.
Setting the warning speed
Once enabled, a threshold slider appears. A badge above the slider shows the current value.
| Range | 60 – 180 km/h |
| Step | 5 km/h (24 steps) |
| Default | 105 km/h |
The threshold slider is only visible when the chime is enabled.
3.How it triggers
A 5 km/h hysteresis band prevents the chime from flickering on and off when you're hovering near the threshold.
Start condition
The chime starts when your speed reaches the threshold.
Stop condition
The chime stops when your speed drops to the threshold minus 5 km/h or below.
Example (threshold = 105 km/h)
The chime starts at 105 km/h. If you slow to 103 km/h, it keeps playing. It stops only when you drop to 100 km/h (= 105 − 5) or below.
| Speed | Chime state |
|---|---|
| 104 → 105 km/h | Starts |
| 105 → 103 km/h | Still playing (within hysteresis) |
| 103 → 100 km/h | Stops (below threshold − 5) |
| 100 → 105 km/h | Starts again |
4.When it works
The chime works during live OBD2 monitoring and during playback of recorded sessions.
| Condition | Chime |
|---|---|
| OBD2 connected, recording | Active |
| OBD2 connected, not recording | Active |
| OBD2 not connected | No speed data → inactive |
During playback
The chime also works during playback of recorded sessions. It uses the saved ECU speed, falling back to GPS speed if unavailable.
If you don't want the chime during playback, temporarily disable it in Settings.
5.Audio behavior
The chime plays through system audio — your device speaker or connected Bluetooth output.
| Output | System audio (speaker / Bluetooth) |
| Mixing | Plays alongside music and navigation audio |
The chime runs in mix mode, so it plays simultaneously with music apps, navigation voice guidance, and hands-free calls. It won't interrupt or pause other audio.
6.The story behind the "kinkon" chime
From the 1970s through around 2000, Japanese vehicle safety standards required passenger cars to sound a speed warning chime — commonly known as "kinkon" — when exceeding 105 km/h. The mandate was dropped in a 2000 regulation update, but the sound remains iconic for many Japanese drivers.
This feature is a digital recreation of that warning device. The default threshold of 105 km/h comes directly from the original standard.
7.Tips
Suggested thresholds
| Use case | Suggested threshold |
|---|---|
| Highway speed-limit compliance | 100–105 km/h |
| City speed-limit reminder | 60–70 km/h |
| Retro JDM experience | 105 km/h (matches the original) |
| Personal best alert on track | Any speed you like |
- The chime follows ECU vehicle speed. If your speedometer is off due to tire size changes, the chime trigger will be affected too.
- The app must be in the foreground. The chime won't sound in the background.
- When connected to Bluetooth speakers, the chime plays through the connected device.
8.FAQ
I enabled the chime but it doesn't sound
Check that: you're connected to an OBD2 adapter, the engine is running, your speed exceeds the threshold, and your device isn't muted.
The chime flickers on and off near the threshold
A 5 km/h hysteresis band prevents most chattering. If it's still noticeable, try raising the threshold slightly.
The chime is annoying during playback
Temporarily disable it in Settings or raise the threshold.
Can I set the threshold in mph?
Currently, the threshold is set in km/h only.
Can I change the chime sound?
The chime sound is currently fixed and cannot be changed.
Does the chime interrupt my music?
No. The chime mixes with other audio, so music keeps playing.
Any differences between iOS and Android?
None. It works identically on both platforms.
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