What to Do When eSIM is Not Working
Start by classifying the symptom
eSIM issues fall into 4 types:
- A. Install fails (QR not recognized, download fails)
- B. Installed but no signal (No Service / emergency only)
- C. Signal but no data (messaging/maps don’t work)
- D. Data is slow or drops (speed cap, network switching)
Check in this order and most issues are fixed.
0) Quick 30-second check (do first)
- Airplane mode ON → 10 sec → OFF
- Reboot once
- Confirm travel eSIM line is ON
- Confirm mobile/cellular data is set to travel eSIM
A. eSIM won’t install
1) Wi‑Fi
Profile download is more reliable on Wi‑Fi. Try different Wi‑Fi and retry.
2) QR not recognized
- Max brightness, no reflection/blur, 20–30 cm distance
- If still no: use manual entry (SM‑DP+ / activation code)
iPhone: Settings > Cellular > Add eSIM > Enter details manually
3) Device (support / lock)
- Check eSIM support (EID): eSIM compatible devices
- Carrier lock can block overseas eSIM
B. No signal (No Service)
1) Network selection (auto / manual)
Auto can pick the wrong network abroad.
- iPhone: Settings > Cellular > Network selection > Auto OFF → pick network manually
- Android: Settings > Connections > Mobile network > Operator (or similar)
2) Plan supports your country?
“Japan plan” tested in a transit country may show no signal. Check supported countries and start condition.
C. Signal but no data (most common)
1) Data roaming ON (travel eSIM)
Most travel eSIMs need data roaming ON for data.
- iPhone: Settings > Cellular > travel eSIM > Data roaming ON
- Android: Settings > Connections > Mobile network > Data roaming ON
2) APN required?
Some providers need APN. If provider email/app says so, enter it and reboot.
3) Data line not on home USIM
If data goes through home USIM on dual SIM, you risk roaming charges.
- Confirm cellular/mobile data is travel eSIM
- Allow cellular data switching OFF if possible
D. Data slow or dropping
1) Speed policy (cap / throttled unlimited)
Many plans are “high-speed nGB then throttled unlimited.” After high-speed is used, speed drops.
2) Try another network (manual selection)
Quality varies by carrier in the same area. Try selecting another operator manually.
3) Congestion
Subways, venues, busy areas at peak times can be slow.
When to contact provider
Contact if:
- Installed but activation doesn’t complete for a day+
- In a supported country but no signal at all
- APN / activation errors persist after following instructions
Include: device model, OS, eSIM plan name/order number, location (country/city) and time, signal bar screenshot, mobile data line and data roaming settings.
See also When eSIM data doesn’t work abroad.