What is the difference between a fault and a warning on the SUN SG04LP3/SG05LP3 Hybrid?

A fault cuts the unit's output and the red LED stays solid — this page lists 25 of them for the SUN SG04LP3/SG05LP3 Hybrid. The SUN SG04LP3/SG05LP3 Hybrid manual defines no separate warning table — every listed code stops operation. Resolve the cause of a fault before restarting; warnings can usually be cleared while the unit runs.

Where do these codes come from?

Every entry was transcribed from 038_BManual_SUN-5_6_8_10_12K-SG04LP3-EU_20260319_en_081932c1.pdf, 040_BManual_SUN-3_4_5_6_8_10_12K-SG05LP3-EU-SM2_20260319_en_b0183b7d.pdf, 044_BManual_SUN-14_15_16_18_20K-SG05LP3-EU-SM2_20260319_en_ac7cdbd1.pdf — DEYE's official documentation. Each row cites its source manual (and page where printed), so you can verify the wording before acting on it.

DEYE SUN SG04LP3/SG05LP3 Hybrid Error Codes: Causes & Fixes (25 codes)

This is the complete fault table for the DEYE SUN SG04LP3/SG05LP3 Hybrid Inverter family — 25 codes shared by 17 model numbers, transcribed from the official manual. On DEYE units, a fault code means the unit has cut its output and the red LED stays solid; a warning flashes the red LED while the unit keeps running.

Also coversSUN-5K-SG04LP3-EUSUN-6K-SG04LP3-EUSUN-8K-SG04LP3-EUSUN-10K-SG04LP3-EUSUN-12K-SG04LP3-EUSUN-3K-SG05LP3-EU-SM2SUN-4K-SG05LP3-EU-SM2SUN-5K-SG05LP3-EU-SM2SUN-6K-SG05LP3-EU-SM2SUN-8K-SG05LP3-EU-SM2SUN-10K-SG05LP3-EU-SM2SUN-12K-SG05LP3-EU-SM2SUN-14K-SG05LP3-EU-SM2SUN-15K-SG05LP3-EU-SM2SUN-16K-SG05LP3-EU-SM2SUN-18K-SG05LP3-EU-SM2SUN-20K-SG05LP3-EU-SM2

Last checked against the official manuals on July 11, 2026.

Fault(25)— output stops · red LED solid

Fault codes (25)output stops · red LED solid

F01

PV Input Polarity Reversed.

Fault

DC input polarity reverse fault - the PV DC input is connected with reversed polarity.

CauseThe PV input positive and negative cables are connected in reverse.

Recommended fix1. Check the PV input polarity. 2. Seek help from us if it cannot go back to the normal state.

Source:038_BManual_SUN-5_6_8_10_12K-SG04LP3-EU_20260319_en_081932c1.pdf· page 45040_BManual_SUN-3_4_5_6_8_10_12K-SG05LP3-EU-SM2_20260319_en_b0183b7d.pdf· page 45044_BManual_SUN-14_15_16_18_20K-SG05LP3-EU-SM2_20260319_en_ac7cdbd1.pdf· page 45

F07

DC Start Failure.

Fault

DC_START_Failure - the BUS voltage cannot be built from PV or battery.

CauseThe internal BUS voltage could not be built up from the PV or battery input.

Recommended fixRestart the inverter. if the fault still exists, contact us for help.

F13

Working Mode Change.

Fault

Working mode change - the inverter's working mode has been changed.

CauseThe grid type or frequency setting has been changed, the battery mode has been changed to 'No battery' mode, or (on some old firmware versions) the system's work mode has been changed.

Recommended fixGenerally it disappears automatically. if it stays the same, turn off the DC switch and AC switch, wait for one minute, then turn on the DC/AC switches. Seek help from us if it cannot go back to the normal state.

Source:038_BManual_SUN-5_6_8_10_12K-SG04LP3-EU_20260319_en_081932c1.pdf· page 46040_BManual_SUN-3_4_5_6_8_10_12K-SG05LP3-EU-SM2_20260319_en_b0183b7d.pdf· page 46044_BManual_SUN-14_15_16_18_20K-SG05LP3-EU-SM2_20260319_en_ac7cdbd1.pdf· page 46

F15

AC Overcurrent (Software).

Fault

AC over current fault of software - AC side overcurrent fault detected by software.

CauseThe AC-side current exceeded the software protection limit, typically because the backup load power and common load power are beyond the allowed range.

Recommended fix1. Check whether the backup load power and common load power are within the range. 2. Restart and check whether it is normal. 3. Seek help from us if it cannot go back to the normal state.

F16

AC Leakage Current Fault.

Fault

AC leakage current fault - leakage (residual) current fault.

CauseThe leakage current to ground exceeded the limit, usually due to a PV-side cable ground connection problem.

Recommended fix1. Check the PV side cable ground connection. 2. Restart the system 2-3 times. 3. if the fault still exists, contact us for help.

F18

AC Overcurrent (Hardware).

Fault

AC over current fault of hardware - AC side overcurrent fault detected by hardware.

CauseThe AC-side current exceeded the hardware protection limit, typically because the backup load power and common load power are beyond the allowed range.

F20

DC Overcurrent (Hardware).

Fault

DC over current fault of the hardware - DC side overcurrent fault.

CauseThe DC-side current exceeded the hardware protection limit; a PV module or battery connection problem, or starting the inverter under a high power load in off-grid mode, can trigger it.

Recommended fix1. Check the PV module connection and battery connection. 2. In off-grid mode, starting the inverter with a high power load may report F20 - reduce the connected load power. 3. Turn off the DC switch and AC switch, wait one minute, then turn on the DC/AC switches again. 4. Seek help from us if it cannot go back to the normal state.

F21

BUS Overcurrent.

Fault

Tz_HV_Overcurr_fault - overcurrent on the internal high-voltage BUS.

CauseThe DC BUS current exceeded the limit, typically because the PV input current or the battery current setting is too high.

Recommended fix1. Check the PV input current and the battery current setting. 2. Restart the system 2~3 times. 3. if the fault still exists, contact us for help.

F22

Remote Emergency Stop.

Fault

Tz_EmergStop_Fault - the inverter has been shut down remotely.

CauseA remote shutdown command was issued; the inverter is being remotely controlled.

Recommended fixThe inverter is remotely controlled - check the remote control/shutdown source and release the remote stop.

F23

Leakage Transient Overcurrent.

Fault

Tz_GFCI_OC - the leakage (residual) current is in transient overcurrent.

CauseThe leakage current spiked beyond the transient limit, usually due to a PV-side cable ground connection problem.

Recommended fix1. Check the PV side cable ground connection. 2. Restart the system 2~3 times. 3. if the fault still exists, contact us for help.

F24

DC Insulation Failure.

Fault

DC insulation failure - the PV isolation resistance is too low.

CauseThe insulation resistance between the PV array and ground is below the limit; the PV panel connections or the inverter's PE grounding may be faulty.

Recommended fix1. Check that the connection of the PV panels and the inverter is firm and correct. 2. Check whether the PE cable of the inverter is connected to ground. 3. Seek help from us if it cannot go back to the normal state.

F26

DC Busbar Unbalanced.

Fault

The DC busbar is unbalanced - the internal DC BUS voltages are unbalanced.

CauseThe load power of the 3 phases is very different, or there is DC leakage current.

Recommended fix1. Wait for a while and check whether it returns to normal. 2. Restart the system 2~3 times. 3. Seek help from us if it cannot go back to the normal state.

Source:038_BManual_SUN-5_6_8_10_12K-SG04LP3-EU_20260319_en_081932c1.pdf· page 47040_BManual_SUN-3_4_5_6_8_10_12K-SG05LP3-EU-SM2_20260319_en_b0183b7d.pdf· page 47044_BManual_SUN-14_15_16_18_20K-SG05LP3-EU-SM2_20260319_en_ac7cdbd1.pdf· page 47

F29

Parallel CAN Bus Fault.

Fault

Parallel CAN Bus fault - communication fault between paralleled inverters.

CauseIn parallel mode, the parallel communication cable connection or the hybrid inverter communication address setting is incorrect; F29 also appears normally during parallel system startup until all inverters are in ON status.

Recommended fix1. In parallel mode, check the parallel communication cable connection and the hybrid inverter communication address setting. 2. During the parallel system startup period, inverters will report F29; when all inverters are in ON status, it disappears automatically. 3. if the fault still exists, contact us for help.

F34

AC Overcurrent Fault.

Fault

AC Overcurrent fault - the backup load exceeds the allowed power.

CauseThe load connected to the backup port exceeds the allowed power range.

Recommended fix1. Check the backup load connected and make sure it is in the allowed power range. 2. if the fault still exists, contact us for help.

F41

Parallel System Stop.

Fault

Parallel system stop - the parallel system has stopped.

CauseOne hybrid inverter in the parallel system has shut down; all hybrid inverters then report the F41 fault.

Recommended fix1. Check the hybrid inverter work status. 2. if the fault still exists, contact us for help.

F42

AC Line Low Voltage.

Fault

AC line low voltage - grid voltage fault.

CauseThe grid AC line voltage is below the standard voltage range in the specification.

Recommended fix1. Check that the AC voltage is in the range of the standard voltage in the specification. 2. Check whether the grid AC cables are firmly and correctly connected. 3. Seek help from us if it cannot go back to the normal state.

F46

Backup Battery Fault.

Fault

Backup battery fault - the battery status is abnormal or inconsistent.

CauseThe status of the batteries is inconsistent - voltage, SOC or other parameters differ between the batteries.

Recommended fix1. Check each battery's status, such as voltage/SOC and other parameters, and make sure all the parameters are the same. 2. if the fault still exists, contact us for help.

F47

AC Overfrequency.

Fault

AC over frequency - grid frequency out of range (too high).

CauseThe grid frequency is above the range given in the specification.

Recommended fix1. Check whether the frequency is in the range of the specification. 2. Check whether the AC cables are firmly and correctly connected. 3. Seek help from us if it cannot go back to the normal state.

F48

AC Underfrequency.

Fault

AC lower frequency - grid frequency out of range (too low).

CauseThe grid frequency is below the range given in the specification.

F55

DC Busbar Voltage Too High.

Fault

DC busbar voltage is too high - the internal BUS voltage is too high.

CauseThe DC busbar (BUS) voltage is too high because the battery voltage is too high or the PV input voltage is outside the allowed range.

Recommended fix1. Check whether the battery voltage is too high. 2. Check the PV input voltage and make sure it is within the allowed range. 3. Seek help from us if it cannot go back to the normal state.

F56

DC Busbar Voltage Too Low.

Fault

DC busbar voltage is too low - battery voltage low.

CauseThe DC busbar voltage is too low because the battery voltage is too low.

Recommended fix1. Check whether the battery voltage is too low. 2. if the battery voltage is too low, use PV or grid to charge the battery. 3. Seek help from us if it cannot go back to the normal state.

Source:038_BManual_SUN-5_6_8_10_12K-SG04LP3-EU_20260319_en_081932c1.pdf· page 48040_BManual_SUN-3_4_5_6_8_10_12K-SG05LP3-EU-SM2_20260319_en_b0183b7d.pdf· page 48044_BManual_SUN-14_15_16_18_20K-SG05LP3-EU-SM2_20260319_en_ac7cdbd1.pdf· page 48

F58

BMS Communication Fault.

Fault

BMS communication fault - communication with the battery BMS has been lost.

CauseThe communication between the hybrid inverter and the battery BMS is disconnected while the 'BMS_Err-Stop' function is active.

Recommended fix1. if you do not want this to happen, disable the 'BMS_Err-Stop' item on the LCD. 2. if the fault still exists, contact us for help.

F62

DRMs0 Stop.

Fault

DRMs0_stop - the inverter has been stopped by a demand response (DRM0) command.

CauseA Demand Response Mode (DRM0) command is active and has stopped the inverter.

Recommended fix1. Check whether the DRM function is active. 2. Seek help from us if it cannot go back to the normal state after restarting the system.

F63

Arc Fault.

Fault

ARC fault - a PV DC arc fault was detected.

CauseAn electric arc was detected on the PV module cabling.

Recommended fix1. Check the PV module cable connection and clear the fault. 2. Seek help from us if it cannot go back to the normal state.

F64

Heat Sink High Temperature.

Fault

Heat sink high temperature failure - the heat sink temperature is too high.

CauseThe heat sink temperature exceeded the limit; the working environment temperature may be too high.

Recommended fix1. Check whether the working environment temperature is too high. 2. Turn off the inverter for 10 minutes and restart. 3. Seek help from us if it cannot go back to the normal state.

Still seeing a code on your SUN SG04LP3/SG05LP3 Hybrid?

Send us the code on your screen and a DEYE technician will reply with the exact steps for your unit. Support is free for life — a first diagnosis never needs a callout.

Message a technician on WhatsApp Call +971542899793 or use the contact form

Keep troubleshooting

Related devices

Common questions about SUN SG04LP3/SG05LP3 Hybrid error codes

What is the difference between a fault and a warning on the SUN SG04LP3/SG05LP3 Hybrid?: A fault cuts the unit's output and the red LED stays solid — this page lists 25 of them for the SUN SG04LP3/SG05LP3 Hybrid. The SUN SG04LP3/SG05LP3 Hybrid manual defines no separate warning table — every listed code stops operation. Resolve the cause of a fault before restarting; warnings can usually be cleared while the unit runs.
Which model numbers does this page cover?: The SUN SG04LP3/SG05LP3 Hybrid shares its firmware and fault table with 16 other model numbers: SUN-5K-SG04LP3-EU, SUN-6K-SG04LP3-EU, SUN-8K-SG04LP3-EU, SUN-10K-SG04LP3-EU, SUN-12K-SG04LP3-EU, SUN-3K-SG05LP3-EU-SM2, SUN-4K-SG05LP3-EU-SM2, SUN-5K-SG05LP3-EU-SM2, SUN-6K-SG05LP3-EU-SM2, SUN-8K-SG05LP3-EU-SM2, SUN-10K-SG05LP3-EU-SM2, SUN-12K-SG05LP3-EU-SM2, SUN-14K-SG05LP3-EU-SM2, SUN-15K-SG05LP3-EU-SM2, SUN-16K-SG05LP3-EU-SM2, SUN-18K-SG05LP3-EU-SM2, SUN-20K-SG05LP3-EU-SM2. If your unit is any of these, every code on this page applies to it.
Where do these codes come from?: Every entry was transcribed from 038_BManual_SUN-5_6_8_10_12K-SG04LP3-EU_20260319_en_081932c1.pdf, 040_BManual_SUN-3_4_5_6_8_10_12K-SG05LP3-EU-SM2_20260319_en_b0183b7d.pdf, 044_BManual_SUN-14_15_16_18_20K-SG05LP3-EU-SM2_20260319_en_ac7cdbd1.pdf — DEYE's official documentation. Each row cites its source manual (and page where printed), so you can verify the wording before acting on it.

Compiled from official DEYE user manuals. Always consult your device manual and a qualified technician before performing repairs.

How to read the severity labels

Fault codes (25)output stops · red LED solid

PV Input Polarity Reversed.

DC Start Failure.

Working Mode Change.

AC Overcurrent (Software).

AC Leakage Current Fault.

AC Overcurrent (Hardware).

DC Overcurrent (Hardware).

BUS Overcurrent.

Remote Emergency Stop.

Leakage Transient Overcurrent.

DC Insulation Failure.

DC Busbar Unbalanced.

Parallel CAN Bus Fault.

AC Overcurrent Fault.

Parallel System Stop.

AC Line Low Voltage.

Backup Battery Fault.

AC Overfrequency.

AC Underfrequency.

DC Busbar Voltage Too High.

DC Busbar Voltage Too Low.

BMS Communication Fault.

DRMs0 Stop.

Arc Fault.

Heat Sink High Temperature.

Still seeing a code on your SUN SG04LP3/SG05LP3 Hybrid?

Keep troubleshooting

Related devices

Common questions about SUN SG04LP3/SG05LP3 Hybrid error codes