Inverter Fault Library

GoodWe Error Codes

GoodWe inverter error codes for grid, isolation, temperature and internal faults, with clear guidance on self-recovery versus service.

Independent · manufacturer-neutralReviewed June 2026Source: GoodWe docs & field referencesOur methodology
Manufacturer
GoodWe
Codes documented
20
Source
GoodWe docs & field references
Scope
Reference only

An independent reference compiled by Solar Analytica from GoodWe documentation and field sources. GoodWe shows faults as a numbered error code and/or a named fault depending on the model — on an LCD unit, short-press the front button and scroll to “Error”/“Fault”; on ET/EH/EHB hybrid units, check Alarms in the SolarGo app or the SEMS portal. Where a fault has both a number and a name, we list them together, and both are searchable. Safety note: earth and insulation faults (Isolation, Ground I, PE Loss) need a licensed electrician — don't keep resetting them; and for a PV over-voltage, switch off the DC isolator before anything else.

Key takeaways
  • 20 GoodWe fault and alarm codes, documented in plain English.
  • Compiled from manufacturer documentation — independent and not affiliated with GoodWe.
  • Codes involving DC/AC isolators, wiring or opening the unit are licensed-electrician work — when in doubt, call your installer.

20 of 20 codes

  • 1

    SPI failure

    An internal communication (SPI bus) failure inside the inverter.

    What to do

    Restart the inverter (AC off, DC isolator off, wait 5 minutes, reverse). If it returns, it needs servicing — contact your installer or GoodWe.

  • 2

    EEPROM R/W failure

    A read/write failure on the inverter's memory chip.

    What to do

    Restart the inverter. If the fault remains, it needs servicing — contact your installer or GoodWe.

  • 3 · Fac Failure

    Grid frequency fault

    The grid frequency is outside the inverter's permissible range.

    What to do

    The inverter restarts automatically once the grid frequency returns to normal. If it's frequent — common when running off a generator — contact your network operator.

  • 7 · 25

    Relay check failure

    The inverter's grid relay failed its self-check.

    What to do

    Restart once. If it returns, the relay or power board needs replacement by a technician.

  • 12

    LCD communication failure

    A communication error between the LCD/display and the master DSP.

    What to do

    Restart the inverter. If it persists, contact your installer or GoodWe.

  • 13

    DC injection high

    The DC component of the AC output current exceeds the inverter's limit.

    What to do

    Restart the inverter. If the fault recurs, contact your installer or GoodWe.

  • 14 · Isolation Fail

    Isolation failure

    Insulation resistance between the PV array and ground is too low — most common in rain or high humidity.

    What to do

    If it clears once dry, moisture is getting in. An installer should switch off the DC isolator and measure the impedance from PV+ and PV− to earth; if it's low, inspect the PV wiring insulation and MC4 connectors for water ingress. Don't keep resetting it.

  • 15 · Vac Failure

    Grid voltage fault

    The grid voltage is outside the acceptable range for the inverter.

    What to do

    Often self-restores when the grid returns to range. If it's frequent, your network voltage may be high — contact your installer or network operator; protection settings may need review (with the operator's consent).

  • 16

    External fan failure

    The external cooling fan has faulted.

    What to do

    Check the fan and air vents for blockage. If the fan is faulty it needs replacement — contact your installer.

  • 17 · PV Over Voltage

    PV over-voltage

    The PV array voltage exceeds the inverter's maximum input.

    What to do

    Switch off the DC isolator. The string likely has too many panels in series — your installer must re-check the string sizing against the inverter's maximum input voltage.

  • 19 · Over Temperature

    Over temperature

    The inverter's operating temperature has exceeded its safe limit.

    What to do

    Improve ventilation per the install guidelines, keep the unit out of direct sun and confined spaces, and check the fans aren't blocked.

  • 20

    Internal fan fault

    An internal cooling-fan fault (IFAN).

    What to do

    Restart once. If it persists, the internal fan needs service — contact your installer or GoodWe.

  • 21

    DC bus high

    The internal DC bus voltage is too high.

    What to do

    Restart the inverter. If it recurs, contact your installer or GoodWe.

  • 22 · Ground I Fail

    Ground (residual) current failure

    Residual-current (earth-leakage) protection has tripped — current is leaking to ground.

    What to do

    Switch off the DC isolator and have an installer inspect the PV string wiring insulation for wear or damage. If it persists after reconnection, call a specialist — don't keep resetting an earth fault.

  • 23 · Utility Loss

    Utility (grid) loss

    Loss of connection between the inverter and the utility grid — an outage or a disconnection.

    What to do

    Check the Solar Supply Main Switch and the AC isolator are on, and confirm the grid is working. If the grid is fine and it persists, have an installer check the AC wiring.

  • 24 · 31

    AC HCT (current sensor) failure

    The AC current sensor (HCT) has failed.

    What to do

    Restart once. If it remains, the current sensor needs service — contact your installer or GoodWe.

  • 26 · 32

    GFCI failure

    A failure in the leakage-current (GFCI) detection circuit.

    What to do

    Restart once. If it remains, the safety detection circuit is compromised and needs repair — arrange it promptly; don't ignore it.

  • 30

    Reference 1.5 V failure

    The internal 1.5 V reference voltage is out of range.

    What to do

    Restart the inverter. If it persists, it needs servicing — contact your installer or GoodWe.

  • PE Loss

    Protective earth (PE) loss

    A missing or faulty protective-earth connection — possibly loose wiring, corrosion, or grounding-system damage.

    What to do

    This is an electrical-safety fault — have a licensed electrician diagnose and repair the grounding connection. Don't keep resetting it.

  • Device Failure

    Internal device failure

    A general internal device failure (shown for faults outside the listed codes).

    What to do

    Restart the inverter once. If it persists, note the exact code shown and contact your installer or GoodWe.

Good to know

Frequently asked

Where do these GoodWe fault codes come from?
We compile them from publicly available GoodWe inverter documentation and field references, then rewrite each entry in plain English. Solar Analytica is independent and not affiliated with GoodWe.
Can I clear these faults myself?
Some clear automatically once conditions return to normal. Anything involving DC isolators, AC switches, wiring or opening the unit is licensed-electrician work — if in doubt, contact your installer rather than working on a live system.
My exact code isn't listed — why not?
Firmware and model variants differ, and manufacturers occasionally revise their codes. We document the most common ones; if yours isn't here, check your inverter's manual or ask your installer.
How current is this reference?
Last reviewed June 2026. We revise it when the underlying manufacturer documentation changes.