Also applies to:SUN-120K-G01P3-EU-BM8SUN-125K-G01P3-EU-BM8SUN-130K-G01P3-EU-BM8SUN-135K-G01P3-EU-BM8SUN-136K-G01P3-EU-BM8
What it means
Relay open circuit fault — At least one AC relay cannot close.
Cause: At least one relay cannot be closed - a relay fault or a faulty relay driver signal (old inverters have no relay detection function).
How to fix it
- 1Check the relays and their driver signals
- 2Restart the inverter; if the fault still exists, contact your installer or Deye service.
Source: 041_BManual_SUN-120_125_130_135_136K-G01P3-EU-BM8_20251021_en_a2166559.pdf, p.62
Also applies to:SUN-7K-G02P1-EU-AM2SUN-7.5K-G02P1-EU-AM2SUN-8K-G02P1-EU-AM2SUN-9K-G02P1-EU-AM2SUN-10K-G02P1-EU-AM2SUN-10.5K-G02P1-EU-AM2
What it means
Dc boost soft start — DC boost soft-start fault. Marked 'Not available' in the manual for these models.
Cause: Fault of the DC boost soft-start stage; this code is not used on these single-phase models.
How to fix it
- 1Marked 'Not available' in the manual - this code is not used on these models.
- 2If it is displayed nonetheless, restart the inverter and contact your installer or Deye service.
Source: 065_BManual_SUN-7_7.5_8K-G02P1-EU-AM2_20260625_en_4466f08b.pdf, p.52 · 032_BManual_SUN-9_10_10.5K-G02P1-EU-AM2_20260625_en_df0f2106.pdf, p.52
Also applies to:SUN-60K-G03SUN-70K-G03SUN-75K-G03SUN-80K-G03SUN-90K-G03SUN-100K-G03SUN-110K-G03SUN-60K-G01P3-EU-AM8-LV+7
What it means
Relay open circuit fault — At least one AC relay cannot close.
Cause: At least one relay cannot be closed - a relay fault or a faulty relay driver signal (old inverters have no relay detection function).
How to fix it
- 1Check the relays and their driver signals
- 2Restart the inverter; if the fault still exists, contact your installer.
Source: 033_BManual_SUN-70_75_80_90_100_110K-G03_20260702_en_a9db1e1b.pdf, p.62 · 042_BManual_SUN-120_125_130_135_136K-G01P3-EU-AM8_20260702_en_05f936e3.pdf, p.61 · 060_BManual_SUN-60_70_75K-G01P3-EU-AM8-LV_20260701_en_f559aeec.pdf, p.61 · +1 more official manuals
Also applies to:SUN-6K-G06-LV-P1SUN-8K-G06-LV-P1SUN-6K-G06P3-EU-BM2-LV-P1SUN-8K-G06P3-EU-BM2-LV-P1SUN-10K-G05-LVSUN-12K-G05-LVSUN-15K-G05-LVSUN-15K-G06P3-EU-BM2-P1+48
What it means
Relay open circuit fault — At least one grid relay cannot close (open circuit detected).
Cause: A relay or its driver signal is faulty, so at least one relay cannot be closed (old inverters have no relay detection function).
How to fix it
- 1Check the relays and their driver signals.
- 2Restart the inverter; if the fault still exists, contact your installer or Deye service.
Source: 063_BManual_SUN-6K-G06-LV-P1_20250923_en_30a96699.pdf, p.58 · 036_BManual_SUN-3_4_5_6_7_8_9_10_12_15K-G06P3-EU-BM2_20250506_en_0eb78440.pdf, p.57
Also applies to:SUN-1K-G04P1-EU-AM1SUN-1.5K-G04P1-EU-AM1SUN-2K-G04P1-EU-AM1SUN-2.2K-G04P1-EU-AM1SUN-2.5K-G04P1-EU-AM1SUN-2.7K-G04P1-EU-AM1SUN-3K-G04P1-EU-AM1SUN-3.3K-G04P1-EU-AM1+15
What it means
Dc boost soft start — DC boost converter soft-start fault (marked 'Not available' on these models).
Cause: The DC boost stage failed its soft-start; this code is not used on these single-phase models.
How to fix it
Marked 'Not available' on these single-phase models - the code is not used.
Source: 031_BManual_SUN-1_1.5_2_2.2_2.5_2.7_3_3.3_3.6_4K-G04P1-EU-AM1_20260624_en_15adc00c.pdf, p.54
Also applies to:SUN-5K-SG01HP3-EU-AM2SUN-6K-SG01HP3-EU-AM2SUN-8K-SG01HP3-EU-AM2SUN-10K-SG01HP3-EU-AM2SUN-12K-SG01HP3-EU-AM2SUN-15K-SG01HP3-EU-AM2SUN-20K-SG01HP3-EU-AM2SUN-25K-SG01HP3-EU-AM2+9
What it means
AC Slave Contactor Fault — AC_SlaveContactor_Fault - the slave AC contactor reported a fault.
Cause: The slave AC contactor failed its check; an incorrect grid orientation (wiring) can cause it.
How to fix it
- 1Check whether the grid orientation is correct
- 2Restart the inverter 3 times and restore the factory settings.
Source: 037_BManual_SUN-5_6_8_10_12_15_20_25K-SG01HP3-EU-AM2_20260224_en_9ef2717c.pdf, p.50 · 050_BManual_SUN-29.9_30_35_40_50K-SG01HP3-EU-BM3_4_20260224_en_544e1b2f.pdf, p.51 · 062_BManual__SUN-60_70_75_80K-SG02HP3-EU-EM6_20260224_en_38cbc9f6.pdf, p.51
Also applies to:RW-L2.5ARW-L5.1RW-L10.2RW-F16SE-F5SE-F5 PlusSE-F5 ProSE-F12+7
What it means
PCS communication fails — The communication link between the battery and the inverter/PCS dropped.
Cause: The CAN link (500 kbps) between the battery COM port and the inverter's BMS port failed - loose or miswired cable, wrong pin order, or the wrong battery-protocol selection on the inverter.
How to fix it
- 1Check the communication cable from the battery COM port to the inverter's BMS port, verify the pin order against the manual, and select the correct lithium/CAN protocol on the inverter.
- 2Restart both units.
Source: 093_Deye_RW-L2.5A_User_Manual_EN_89188fb8.pdf, p.10 · 019_Download_4a609b7e.pdf, p.10 · 021_Download_f81ba1e7.pdf, p.10 · +6 more official manuals
Also applies to:GB-A
What it means
MBMS_SAM_SIG_ID_PCS_ERROR_STATE — The PCS RS485 communication fails (PCS error state signal).
Cause: The battery stopped receiving valid RS485 communication from the PCS, or the PCS is signalling an error state.
How to fix it
- 1Check the RS485 cable and pinout to the PCS and clear any fault on the PCS side, then restart.
- 2Contact Deye support if it persists.
Source: 008_deye_ess_user_manual_gb_a_jpnen_v02_20250829_3fea617e.pdf, p.13