2064 on a Huawei SUN2000-L1 single-phase hybrid-ready inverter: Unrecoverable fault on an internal circuit (Major); Cause IDs 1-12 (boost short, control circuit, RCD sensor, EEPROM, relay, DC bus...)
Short answer
On a Huawei inverter, 2064 means: Unrecoverable fault on an internal circuit (Major); Cause IDs 1-12 (boost short, control circuit, RCD sensor, EEPROM, relay, DC bus...). The inverter stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: Unrecoverable fault on an internal circuit (Major); Cause IDs 1-12 (boost short, control circuit, RCD sensor, EEPROM, relay, DC bus...).
Part involved: internal circuits.
Likely causes:
- Internal hardware fault.
Is it safe?
| Does the inverter stop? | Yes |
|---|---|
| Severity | Fault — needs a manual reset once the cause is fixed |
| Engineer needed? | Yes |
The inverter stops until the fault clears or is reset.
Resetting itself: no.
Manual reset: AC and DC switches off 5 min then on; else support.
What you can check
- Read the full code and message on the inverter screen or in the FusionSolar app and note the date/time for your installer.
- Check the inverter's AC isolator next to the inverter and the solar/battery breaker in the consumer unit are ON (do not reset a breaker that trips again - call your installer).
- Huawei's troubleshooting step 'turn off the AC output switch and DC input switch, wait 5 minutes, turn on' is written for qualified personnel - ask your installer unless they have shown you this sequence.
What the engineer will check
- Power-cycle; if persists, RMA via Huawei.
Who to ask for: MCS-certified solar PV installer (DC/string work) or the original installer.
Certification: Work on DC strings and inverter enclosures: competent PV installer (MCS-certified installer for warranty/SEG continuity); electrical work notifiable under Part P (England & Wales) or equivalent.
What you might notice
Sources
- SUN2000-(2KTL-6KTL)-L1 User Manual (Copy, AU) ↗ · Issue 06 · page PDF p.95 · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026