Why is my Probe offline on the Dashboard or not coming back online?

A Probe may appear offline on the Dashboard, go offline after previously being online, or fail to come back online after a reboot, power cycle, or network change. In some cases the issue is internet quality or site network settings. In others, the Probe may not have completed startup properly.

Normal behaviour: A brief offline state on the Dashboard of up to about 1 minute can be normal, especially if the blue LED on the Probe is on. After startup, allow up to 5 minutes before treating it as a problem.

Agent triage — ask these first

Ask all three before troubleshooting:

"Is the Probe's physical blue LED on or off right now?"
- If unsure: Ask — "Does the Probe's physical blue LED indicator go blue, or does the online indicator in the Dashboard show yellow instead of green?"
- If still unsure: Continue — note that blue LED status is uncertain and proceed with both startup and network checks.
"Did this happen after a network change, reboot, or power cycle — or did the Probe go offline on its own during normal use?"
- If unsure: Ask — "Was anything changed recently — cables moved, router repositioned, network settings updated, or did the Probe lose power?"
- If still unsure: Continue — treat as an unplanned offline event and proceed with startup checks first.
"How are you running the measurement — through the Cloud Dashboard, a local dashboard, or Modbus/scripts?"
- If unsure: Ask — "Are you clicking buttons on a web page to run the measurement, or is it triggered automatically by a script or PLC?" They can also check by opening dashboard.pulsenics.com — if that's where they run measurements, it's the Cloud Dashboard.

Use the answers to route:

Situation	Route
Blue LED off + never came online after startup	→ Likely startup / boot issue (not always conclusive). Start with startup checks below.
Blue LED on + went offline during normal use	→ Network / connectivity issue. Start with network checks below.
Went offline after a network change	→ Network / site compatibility issue. Start with network checks below.
Probe reachable locally but Dashboard shows offline	→ Dashboard reporting or network issue. Start with network checks below.
First-time deployment, never came online	→ Start with startup checks, then network checks. Escalate sooner if both pass.
Established setup that suddenly went offline	→ Start with network checks. Check whether anything changed in the environment.

Immediate workaround

If testing needs to continue while the issue is investigated:

If the Probe is reachable locally via its hotspot, it may still be collecting data even if the Dashboard shows offline
Power cycling the Probe resolves the offline state in many cases and is always the right first step

Confirm after: After a power cycle, allow up to 5 minutes for the Probe to come fully online before assessing whether the issue is resolved.

Startup checks — do these first if the blue LED is off

Confirm the Probe has power (check power LEDs)
Power cycle the Probe and wait up to 5 minutes for full startup to complete
Confirm the expected startup LED sequence completes properly
If using Wi-Fi, confirm the Wi-Fi button is pressed in on the Probe
Check whether the Probe presents a Wi-Fi hotspot after startup:
- Hotspot name: Pulsenics Wifi Setup_PUXXX where PUXXX is your Probe's unit number (e.g. PU198 or PU201)
- Password: PulseActivate!
- If the hotspot does not appear, startup may not have completed properly

Still offline after power cycle?

If the Probe remains offline after a full power cycle and 5-minute wait, do not attempt further hardware changes. Use the routing below:

Situation after power cycle	Route
Probe came back online	→ Good. Run 2–3 measurements to confirm stability.
Probe still offline + blue LED off	→ Startup did not complete. Collect escalation checklist below and contact Pulsenics. Do not attempt to connect the Probe directly to a laptop or make further network changes.
Probe still offline + blue LED on	→ Startup completed but network connection is not establishing. Proceed with network checks below. If the Probe hotspot is not appearing or the setup page is not loading, see: Can't access the Pulsenics Network Setup page? (Hotspot unavailable or setup page not loading)
Probe still offline + LED status unknown	→ Proceed with network checks below and collect escalation checklist to have ready.

Network checks — do these if startup appears normal

Confirm the internet connection at the router is stable
Check whether the Dashboard online indicator is yellow instead of green — this indicates the Probe is connecting but not maintaining a stable connection
Check signal strength at the Probe setup page (Wi-Fi only):
- Connect to the Probe's hotspot (see hotspot name and password above)
- Open http://setup.pulsenics.com or 1.0.0.1
- Open the Wi-Fi setup dropdown and note the dBm value
- General guidance: -50 dBm or better is strong; -50 to -70 dBm is marginal; -70 dBm or worse is weak
If Wi-Fi signal is weak or marginal, try Ethernet instead
Check router and antenna placement relative to metal enclosures, walls, or obstructions
Confirm whether the issue started after moving to a client network — if so, the client network may have special requirements (whitelisting, MTU settings, static IP)
If available, test on the Pulsenics-provided InHand IR302 router (black and green square router with antennas) to isolate whether the issue is site-network-specific

Confirm after: After any network change, allow up to 5 minutes and run at least one full experiment to confirm the Probe remains stably online.

Network-specific consideration

In some cases the Probe works correctly on the Pulsenics-provided router but remains offline on the client network. This points to site-specific requirements such as compatibility settings, whitelisting, or MTU configuration. If this is the case, review the network setup with the client's IT team and Pulsenics support.

Before escalating — collect this information

If the issue continues after startup and network checks, gather the following before contacting Pulsenics:

Blue LED status and whether the startup LED sequence completed
Connection type (Wi-Fi / Ethernet / company network)
Signal strength reading in dBm (Wi-Fi only)
Whether the Dashboard online indicator is yellow or green
Whether the issue is on a first-time deployment or an established setup
Whether the Probe works on the Pulsenics router but not the client network
Whether CMUs are also not being reported (if Probe is online but CMUs are offline, see the CMU offline article)
Interface method (Cloud Dashboard / local / Modbus)
What has already been tried and what effect it had

Prevention

Use a stable network connection with reliable signal
Place the router where it has strong, consistent signal
Document client network requirements before deployment
Keep track of whether the Probe is configured for DHCP or static IP
Use Ethernet when Wi-Fi stability is uncertain

Escalate if

Flag for further review if:

The Probe repeatedly goes offline and does not recover after troubleshooting
No data or messages resume after restart and network checks
The Probe works on the Pulsenics router but not the client network — first review with the client's IT team, then contact Pulsenics
The issue is blocking testing or operations (treat as S2 or higher)
The Probe remains offline after restart, startup checks, and network checks
First-time deployment and the Probe has never come online despite passing startup checks

What recovery looks like

Probe appears online on the Dashboard with a green indicator
Live messages resume
Data updates resume
Experiment can start normally
Online status remains stable during repeated use over 2–3 runs

Article status

This is a living troubleshooting note for the symptom Probe offline on the Dashboard or not coming back online. Additional causes, checks, and confirmed resolutions may be added as more cases are identified.

Tags: Probe, offline, Dashboard, connectivity, startup, boot, Wi-Fi, Ethernet, network, router, CMU, LED, IR302