Solar Panels Not Working? A Step-by-Step Troubleshooting Guide

When the monitoring app shows zero, or production looks lower than it should, a few safe checks usually narrow the cause down before you call anyone: the weather and the grid, the inverter’s lights, the breakers and, if needed, a reset. This guide goes through them in order. None of the steps involves going on the roof or opening equipment.

Step 1: Check the Basics

Rule out the outside causes first:

• Is it nighttime? Solar panels don’t produce power in the dark.
• Is the grid down? If your neighborhood has a power outage and you don’t have a battery backup, your solar system will automatically shut off for safety reasons.
• Is there heavy shading? Check for new tree growth, a heavy accumulation of snow, or debris (like a thick layer of leaves) covering the panels.
• Has your internet disconnected? The system may be producing normally while the monitoring app is offline, for example after a new router or a changed Wi-Fi password. If the inverter display shows production, the problem is the connection.

Step 2: Inspect the Inverter Lights and Codes

First, find out which kind of inverter you have. In public installation records for home systems installed in 2023–2025 (Tracking the Sun), 48% used Enphase microinverters (one small unit under each panel, no big box on the wall) and 27% used a SolarEdge inverter (one box on the wall, with an optimizer under each panel). Tesla, about 14% and rising with Powerwall 3, uses one central inverter, and SunPower systems, about 4%, mostly use microinverters.

The inverter usually reports what kind of fault it has, through its lights, a display code or the app. Light colors and codes differ by brand and model, so check the manual for yours.

String Inverters (SolarEdge, SMA, Fronius)

Locate the main inverter box, usually mounted on the side of your house near the electrical meter or in the garage.

• Solid Green Light: Normal operation, producing power.
• Flashing Green Light: Waiting for sufficient sunlight, or grid connecting.
• Solid or Flashing Red Light: System fault. Look at the digital display screen (if applicable) for a specific error code. Document this code—your technician will need it.

Microinverters (Enphase)

Check the Enphase Envoy (Gateway) box.

• You should see solid green LEDs.
• If the lights are red, open your Enphase Enlighten app. It will flag which specific microinverter (and panel) on the roof is failing.

Step 3: Check for Tripped Breakers

A surge or a fault can trip the system’s breakers.

1. Main Electrical Panel: Go to your home’s main breaker box. Look for a breaker labeled “Solar,” “PV,” or “Photovoltaic.” If it is in the middle (tripped) or OFF position, firmly push it all the way to OFF, then snap it back to ON.
2. AC Disconnect Switch: Near your inverter or utility meter, there is usually a grey box with a large lever. Ensure this lever is in the “ON” (usually up) position.
3. Inverter Breakers: Some string inverters have small internal breakers or a dial switch on the bottom. Ensure they are turned to the ON or ‘1’ position.

Step 4: Perform a Hard Reset

If the breakers are fine but the inverter is frozen or showing an error, a hard reset often clears temporary faults. Follow this specific sequence:

1. Turn OFF the Solar breaker in your main electrical panel.
2. Turn OFF the AC Disconnect lever.
3. Turn OFF the DC Disconnect switch (usually a dial on the bottom of the inverter).
4. Wait 5 full minutes to allow the capacitors to discharge.
5. Turn everything back ON in the reverse order (DC Disconnect, then AC Disconnect, then Main Breaker).
6. Wait 10-15 minutes. The inverter needs time to run safety checks before reconnecting to the grid.

Enphase systems have no DC switch on the wall: turning the solar breaker off and on again restarts the microinverters. If the same fault comes back after a reset, don’t keep resetting; note the code and call a technician.

If the company that installed your system has closed

This is more common than most homeowners expect. In the public installation records compiled by Lawrence Berkeley National Laboratory (Tracking the Sun), more than 420,000 home solar systems were installed by companies that have since closed or filed for bankruptcy, SunPower, Titan Solar, Freedom Forever and Sunnova among them.

• Panel and inverter warranties still apply: they come from the manufacturer. Find the brand on the inverter label or in the monitoring app and contact the manufacturer directly.
• The installer’s workmanship warranty is probably gone. If a bankruptcy case is still open, you can file a claim in it.
• Leased systems and PPAs are the responsibility of the company you pay each month, even if the installer is gone.

Our solar installation and repair pages by city list the installers that closed in each city and the companies still active there.

When to Call a Professional

If you have performed a hard reset, verified the breakers are on, and the system is still showing a red light or zero production, it is time to call a certified solar repair company.

Do NOT attempt to:

• Climb the roof to inspect the wiring. DC voltage from solar panels can be lethal.
• Open the inverter casing.
• Attempt to bypass any fuses or disconnects.

Write down the error codes and the steps you’ve already taken. The technician will use them, and it can shorten the visit.