Start with host panel identification, then communicator model, then reporting path (POTS, IP, cellular, dual-path).
Quick diagnostic flow
- Confirm communicator model matches TL255 Install Manual; 3G2055 v3.0 Installation Manual.
- Verify host panel is on the supported list in compatible-peripherals.md.
- Read active troubles on the panel keypad or installer interface.
- Test physical path (Ethernet link, SIM registration, dialer voltage) independent of zone programming.
- Run communication test to central station after local troubles clear.
- Verify account and receiver programming matches programmed phone number, IP, or cellular destination.
Power and supervision
- Corbus/Keybus modules: check AUX/Corbus voltage and enrollment in installer programming.
- Universal dialer-capture: verify Tip/Ring seizure and ~50 VDC on line when panel is idle.
- Dual-path: test each path independently before relying on backup failover.
Network / cellular
- IP: ping gateway, confirm firewall allows outbound to receiver, check cable and link LEDs.
- Cellular: confirm SIM active, APN correct, RSSI acceptable at install location; use antenna extension kit if enclosure blocks signal.
- 3G modules: verify carrier has not sunset 3G in your area — plan LE4010/TL880 LTE migration where required.
IMPASSA communicator service
- Use WT5500
[*, 2] trouble scroll — IMPASSA does not use Neo [902] enrollment.
- For 3G2055/TL2553G, confirm carrier has not sunset 3G; plan LE2077/TL8055 LTE migration.
- After SIM swap, allow up to 15 minutes for re-registration before replacing module.
IMPASSA alt-comms service
[*, 2] on WT5500 — not Neo [902].- Allow 15 min after SIM change before module swap.
After panel swap
Re-enroll the communicator on the new panel, re-download programming, and re-test all reporting paths — communicators are not hot-swappable across panel families without reprogramming.
Source: TL255 Install Manual; 3G2055 v3.0 Installation Manual; host panel installation guide alt-comms sections.