Chapter 2 · Applies to firmware v390 and later · Updated 2026-09-18
Lights, warnings and messages
What the station's lights, display and web pages can tell you, what each message means, and what to do about it.
1. The red light: fault codes
The red light is the one diagnostic that works with no display, no network and no computer. It says what is wrong by a number of flashes.
The red light is
Meaning
On steadily
Starting up: for the first 10 to 20 seconds after power-on the station checks itself. It also stays on for a few seconds while the station recovers from a fault. It goes off (or starts flashing a code) by itself. If it stays on for more than a minute, contact Denko.
Off
Everything is fine, and the station is reporting.
Flashing
A fault code: a group of short flashes (0.15 s on, 0.15 s off), then a pause of about a second, repeated. Count the flashes in one group and look the number up below.
Flashes
Meaning
What to do
1
The firmware recorded an internal error and restarted, or it is running short of memory. The station keeps working.
Note the firmware version (top line of the display) and restart the station once. If 1 flash comes back, contact Denko.
2
The measurement converter reports an error, or measurement data has stopped.
Switch the station off. Check the cable between the antenna unit and the base unit at both ends. Switch it on again, connecting the power last. If it stays, contact Denko.
3
The background signal level is out of range. Too low: the antenna unit is not connected or not working. Too high: very strong electrical interference, or a fault.
Check the cable to the antenna unit. Move the antenna unit away from electrical equipment. If it stays, contact Denko.
4
No network: the station is not connected to Wi-Fi.
With no Wi-Fi saved, the setup screen appears within seconds; with a saved network it cannot reach, after about 5 minutes. Connect it to Wi-Fi from there (chapter 1, section 3).
5
No satellite position yet.
Normal for a while after the first power-on. Otherwise move the base unit, which has the satellite antenna built in, to where it can see more of the sky.
6
The clock is not locked to the satellites yet.
Normal for the first minutes after a position is found. If it never stops, move the base unit to where it can see more of the sky.
7
The measured signal is not filtered the way it should be. The station keeps reporting.
Restart the station. If it stays, contact Denko.
8
The data coming from the antenna unit is corrupted. The station has stopped reporting until it is good again.
As for 2: check the cable at both ends and restart. The station resumes by itself when the data is good again.
Only the most urgent problem is shown. The order is 1, 2, 8, 3, 7, 4, 5, 6, so a station with no network and no satellite position flashes 4, not 5. When you fix one problem, the next one may appear.
2. The white lights: the signal bar
The row of white lights flashes once for each lightning signal the station detects and reports.
The more lights, the stronger the signal compared with the background noise at your site. One light is a weak signal just above the detection level. A full bar is a very strong one, usually a closer or more powerful stroke.
Each flash is short, with a short dark gap after it, so separate strokes can be counted by eye. In a very active storm some flashes are skipped on the lights only; detection and reporting are not affected.
The bar stays dark while the red light shows a fault or the station is holding back its reports. It never suggests the station is reporting when it is not.
Dark white lights with the red light off simply means no lightning signal right now. That is the normal state most of the time.
3. Health codes on the display
The status screen shows the station's health on the line below the IP address, or next to “IP” when the address is shown large (chapter 1, section 2):
Shown
Meaning
OK
Healthy and reporting.
INIT
The first seconds after start, before the station has judged its health. Codes may already be listed after it, for example INIT:nofix.
BAD: + codes
A problem has lasted about 20 seconds, and the station is holding back its reports until it clears. It reports again about 10 seconds after the problem goes away.
OK? + codes
Reporting, but the station has noticed something that does not stop it.
OFF, or OFF? + codes
Denko has switched this station's health check to information only. The station is on and reporting regardless; any codes are shown for information.
Code
Meaning
Red light
nofix
No satellite position since start. For the first 30 minutes the station holds back its reports; after that it reports without a position.
5
nbndlo
Background signal too low: the antenna unit is not connected or not working.
3
nbndhi
Background signal too high: strong interference, or a fault.
3
fedead
The receiver hears only its own noise: the antenna or its amplifier is not working.
3
adc
The measurement converter is not responding correctly.
2
stall
Measurement data has stopped.
2
bband
The signal is not filtered as expected. Advisory: the station keeps reporting.
7
dblbit
The data readout from the antenna unit is corrupted.
8
gnssant
The satellite receiver reports a fault on its antenna. Advisory: the station keeps reporting. Contact Denko if it stays.
—
What to do for each code is the same as for its red-light number in section 1.
4. Wi-Fi setup messages
On the setup screen (bottom line)
Shown
Meaning
no wifi set
No Wi-Fi network is saved on the station yet. Scan the QR code to set one up.
waiting
The station has a saved network it cannot reach at the moment, and no phone or computer has joined the setup network yet.
phone ok
A device has joined the setup network. Continue on that device.
wrong pass
The last attempt to join your saved network failed: wrong password.
no network
The last attempt failed: network not found (wrong name, out of range, or 5 GHz only).
join failed
The last attempt failed: the router did not accept the station (for example a WPA3-only network).
While saving
Network saved / restarting...: the station restarts in a few seconds to join the new network. finishing update / then restarting: it first finishes a firmware update, which can take up to about 2 minutes. In both cases do not switch it off.
On the setup page
Message
What to do
Last attempt failed: wrong password / network not found / could not join
The reason the station could not join the network saved last. Correct the details and save again.
Saved: “The station is restarting and will try to join that network.”
Nothing. If joining fails, the setup network comes back in a few minutes.
Not saved: “That setup form was stale or was not opened from this station.”
The page was opened before the station restarted. Open the setup page again and retype.
Not saved: “The network name must be 1-32 characters, and the password must be either empty (open network) or 8-63 characters.”
Correct the name or password.
Not saved: “That network name or password was too long to receive intact.”
Use a shorter name or password.
“The last save did not reach storage. Nothing was changed.”
Try again. If it repeats, contact Denko.
“This station cannot store networks … Saving will not work.”
Contact Denko.
Erased / Not erased
The result of /wifi/forget. After “Erased” the station restarts, and shows the setup screen at once, since no network is saved any more.
5. Firmware update messages
These appear on the update screen and at http://<IP address>/ota (chapter 1, section 4).
Message
Meaning
checking
Asking the update server whether there is a new version.
downloading v…
Downloading the new version. Keep the power on.
verifying
Checking the downloaded file before using it.
rebooting to new fw
Restarting into the new version. Keep the power on for at least 3 minutes.
idle v… (no update)
Up to date. (idle v… alone: no check yet since the start.)
manifest timeout, transport busy
The update server did not answer, or the network was busy. The station tries again by itself every 3 minutes.
dl retry …, dl timeout …
The download was interrupted. It is retried automatically.
Shown only for a moment: the downloaded file failed its check, could not be written, or the restart into it failed. Nothing was installed. The next message is FAILED ….
FAILED v… (x…) - quarantined
That version failed to install on this station. The station stays on its current version and does not retry that version for now. If it stays, contact Denko.
update deferred (trial not committed)
Normal for about 2 minutes after an update: the new version is still on trial. The station looks for further updates once it has confirmed itself.
update blocked (trial unbought)
The new version could not confirm itself. At the next restart the station goes back to the previous version. If it repeats, contact Denko.
v… skipped (…)
The station is deliberately not retrying that version right now, to protect itself. If you keep seeing it, contact Denko.
explicit_buy rc=… retry …/5
The new version's first attempt to confirm itself did not succeed; it tries again every 30 seconds. Keep the power on.
explicit_buy failed x5 - will roll back
The new version could not confirm itself. At the next restart the station goes back to the previous version. If it repeats, contact Denko.
no A/B partition table
This station cannot be updated over the internet. Contact Denko.
It is connected to Wi-Fi but cannot reach the internet, and it restarts to recover what looks like a stuck connection. Give the network internet access, or connect the station to one that has it.
It restarts once a day
Normal: a scheduled restart.
The setup screen comes and goes by itself
Normal while no network is reachable: after an hour with nobody connecting, the station restarts, tries its networks again, and brings the setup screen back (at once if no network is saved, otherwise after about 5 minutes).
Display dark, station powered
Most likely the station is in USB update mode, because the display button was held at power-on. Switch it off and on without holding the button. If the display stays dark, contact Denko.
Red light flashing and white lights dark in a storm
Expected: the white bar stays dark while there is a fault. Fix the fault shown by the red light first.
DENKO