Where do these Enphase fault codes come from?

We compile them from publicly available Enphase inverter documentation and field references, then rewrite each entry in plain English. Solar Analytica is independent and not affiliated with Enphase.

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.

Inverter Fault Library

Enphase Microinverter Error Codes

Plain-English guide to the events Enphase IQ microinverters report in the app — grid, DC, temperature and reporting — and what each one means.

Independent · manufacturer-neutralReviewed June 2026Source: Manufacturer documentationOur methodology

Manufacturer: Enphase (IQ-series microinverters)
Codes documented: 13
Source: Manufacturer documentation
Scope: Reference only

Enphase IQ-series microinverters don't show numeric fault codes the way a string inverter does. Instead, each unit reports a plain-language event to the IQ Gateway, which you then see against the affected panel in the Enphase app or in Enlighten (the panel turns amber for a warning, red for a fault, or grey when it isn't reporting). Most of these events are the microinverter doing its job — disconnecting for safety when the grid drifts out of spec, or backing off in low light — and clear on their own once conditions return to normal. The list below covers the events Australian owners most commonly see and what each one means in plain English. Safety note: these are reference descriptions only, not repair instructions. A microinverter sits at the panel on the roof and works at the array's full DC and grid AC voltages. Anything involving the DC isolator, AC wiring, opening or handling the unit, or inspecting rooftop connections is licensed-electrician (and, for solar, CEC-accredited installer) work — never attempt it yourself. If an event won't clear, log it with your installer rather than going onto the roof.

Key takeaways

13 Enphase (IQ-series microinverters) fault and alarm codes, documented in plain English.
Compiled from manufacturer documentation — independent and not affiliated with Enphase (IQ-series microinverters).
Codes involving DC/AC isolators, wiring or opening the unit are licensed-electrician work — when in doubt, call your installer.

13 of 13 codes

AC Voltage Out Of Range
Grid voltage too high or too low
The microinverter is measuring AC (grid) voltage outside the limits set by its grid profile, so it disconnects and stops exporting until the grid settles back within range. In Australia high readings are extremely common on long suburban streets at midday when lots of solar is exporting and pushing local voltage up.
What to do
Usually self-correcting — grid voltage varies through the day and the unit reconnects on its own once it is back in spec for a sustained period. If it recurs daily across many panels, it points to a network/voltage problem on your street, which is a matter for your installer and the local network distributor (DNSP), not a fault in the microinverter. Persistent out-of-range readings on a single unit can indicate a faulty microinverter or its AC connection — diagnosis and any wiring work is for a licensed electrician/accredited installer.
AC Frequency Out Of Range
Grid frequency too high or too low
The microinverter is measuring a grid frequency outside its safe operating band (nominal 50 Hz in Australia) and goes offline as required by grid-protection rules. It must stay off until the grid has been continuously within limits for a set period; if frequency strays again during that window, the timer restarts.
What to do
Almost always a grid/network condition rather than a fault in your system, and it clears itself once the grid stabilises. If it affects all panels at once it is a grid event; if it persists on a single unit with the rest fine, the microinverter may be faulty. Any investigation of AC wiring is licensed-electrician work.
Grid Gone
No grid / AC supply detected
The microinverter has disconnected from the grid/mains because it cannot detect a valid supply, so it shuts down. Enphase units are anti-islanding by design and will not produce power without a stable grid present. This appears during a blackout, or when an AC isolator, breaker or RCD on the solar circuit has been switched off.
What to do
If the whole array reports it, check whether there is a power outage; production resumes automatically when the grid returns. If only one or a few panels report it while others are fine, it suggests a wiring or connection issue, or a failed unit. Checking or switching solar isolators/breakers and any AC wiring is licensed-electrician work.
DC Voltage Too Low
Not enough DC input from the panel
The microinverter is seeing DC input voltage from its solar module below the level needed to operate. This is completely normal early morning, late evening, in heavy shade, or on very overcast days. If it appears in good daylight, it can indicate a poor or broken DC connection between the panel and the microinverter, or — on a new system — that a grid profile still needs to be applied at commissioning before the units will produce.
What to do
If it clears as the light improves, no action is needed — it was just low irradiance. If it persists during strong daylight, the panel-to-microinverter DC connection may be loose, damaged or disconnected; inspecting or working on that connection on the roof is licensed-electrician / accredited-installer work. A newly installed system reporting this may simply need its grid profile applied by the installer.
DC Power Too Low
Panel producing too little power
Closely related to DC Voltage Too Low — the microinverter is measuring DC power below its operating threshold. Most often this is just low light (dawn, dusk, shade, cloud). If it occurs in full sun, it can point to a shaded, soiled or underperforming panel, or a degraded DC connection.
What to do
Expected and self-clearing in low-light conditions. If a panel shows it in bright sun while neighbours produce normally, note it for your installer to investigate. Any rooftop or DC-side inspection is licensed-electrician work.
DC Voltage Too High
Too much DC input from the panel
The microinverter reports DC input voltage from the solar module above its rated maximum. On a correctly matched panel/microinverter pairing this is unusual and generally suggests a microinverter malfunction or a module/wiring mismatch.
What to do
Not user-serviceable. If the condition persists, report it to your installer; on the roof, any inspection of the module or DC wiring is licensed-electrician / accredited-installer work.
GFI Tripped
Ground-fault current detected
The microinverter's built-in ground-fault (GFI) sensor has detected leakage current to earth during normal operation and has opened the circuit to protect against a fault. It can be triggered by moisture/weather, but a persistent trip points to damaged module insulation (such as cracked module glass), a damaged connector or cable, or water ingress.
What to do
A one-off after wet weather may clear (your installer can send a reset command via the Enphase app/Enlighten). A repeating GFI trip should be treated as a genuine insulation/earth fault and inspected promptly by a licensed electrician / accredited installer — do not attempt to reset or investigate it yourself on the roof.
DC Resistance Low - Power Off
Insulation resistance to earth too low
An insulation-resistance (IR) sensor in the microinverter measures the resistance to earth from the positive and negative DC inputs. If it drops below the acceptable threshold (around 7 kΩ on IQ units), the unit stops producing and latches off. On IQ8 units this shows as a solid red status LED (after DC power has been cycled), and the gateway keeps reporting the fault until it is cleared. Common causes are moisture ingress, damaged cabling/connectors, or degraded module insulation.
What to do
The condition must be cleared by command from the IQ Gateway (via the Enphase app / Enlighten device conditions and controls, or Enphase support) once the cause is resolved — it will not clear by itself. A short-lived case after rain may resolve, but a recurring or persistent one indicates a real insulation fault that needs a licensed electrician / accredited installer to find and rectify. Locating and repairing the fault on the array is not DIY work.
Over Temperature / Critical Temperature
Microinverter running too hot
An internal temperature measurement inside the microinverter is above its normal range. To protect itself it automatically reduces (derates) its power output, and in extreme cases shuts down, until it cools; full power resumes once the temperature falls to an acceptable level. Note this is an internal reading, not ambient air temperature (IQ8 units run at full power up to about 50 °C ambient and derate above that). It can be driven by very high roof temperatures or restricted airflow behind the panel.
What to do
Normally self-managing — output recovers once the unit cools. If a single unit repeatedly reports high temperature when others nearby don't, it may be failing; report it to your installer. No rooftop intervention should be attempted by the owner.
Microinverter Failed to Report
Gateway has lost contact with a microinverter
The IQ Gateway is no longer receiving data from one or more microinverters over the powerline communication (PLC) link, so the panel shows grey (not reporting). It can be caused by powerline-communication interference (e.g. a surge strip, noise source, or the gateway being plugged into a power board rather than a wall outlet), a tripped solar breaker/isolator, an AC wiring issue, or a failed unit — it does not necessarily mean the panel has stopped producing.
What to do
Often a communication hiccup that resolves on its own or after the gateway is power-cycled. If specific panels stay grey, it can indicate interference from other equipment, a circuit issue, or a faulty microinverter — diagnosis (and any breaker/wiring work) is for a licensed electrician / accredited installer.
Microinverter Not Detected / Not Found
New microinverter not discovered during commissioning
During or after installation the IQ Gateway / Enphase Installer App cannot find a microinverter to add it to the system. This is a commissioning-stage condition (the device shows as "not discovered") rather than a logged operational fault, and usually means the unit isn't yet powered, hasn't been given time to be discovered, or its serial wasn't scanned correctly.
What to do
An installer task: confirm the unit is installed on a powered panel, allow time for discovery, then re-scan/provision it in the Enphase Installer App (the app provides on-screen guidance when a device fails to be discovered). Any work at the array or switchboard is licensed-electrician / accredited-installer work.
Device Produced No Power
No energy generated in the last 24 hours
A microinverter that previously produced has generated no power within the last 24 hours. Causes range across the grid (a profile/voltage/frequency condition keeping it off), the AC side (a tripped breaker or isolator), or a failed unit.
What to do
Check whether a solar breaker/isolator is off and whether the rest of the array is also affected. Widespread cases usually trace to a grid or switchboard issue; an isolated case can mean a failed microinverter or wiring fault. Switching breakers/isolators and any wiring work is licensed-electrician work; otherwise refer it to your installer.
Gateway / Envoy Not Reporting
IQ Gateway not sending data to Enphase
The IQ Gateway (Envoy) itself has stopped uploading data to the Enphase cloud, so the whole system appears offline in the app. This is almost always an internet/connectivity problem (router, Wi-Fi, or the gateway's own connection) rather than a solar production fault — your panels may still be generating normally.
What to do
Owner-safe checks only: confirm your home internet is working (check it on another device), then restart your router and the gateway (mains power cycle, then wait around 10 minutes). If you've changed router or Wi-Fi password, the gateway needs reconnecting via the Enphase app (your installer can guide this). If it stays offline after that, contact your installer.

Sources

Good to know

Frequently asked

Where do these Enphase fault codes come from?: We compile them from publicly available Enphase inverter documentation and field references, then rewrite each entry in plain English. Solar Analytica is independent and not affiliated with Enphase.
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.

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