How do I fix IQ Battery PCU (Power Conversion Unit) Fault on a Enphase?

Check battery temperature and ventilation. Power cycle the battery (follow Enphase power-down sequence) Then: Check firmware version in Enlighten. Update if available

Enphase

Bat PCU Fault

IQ Battery PCU (Power Conversion Unit) Fault

Internal power conversion fault in the IQ Battery 5P.

Common causes

Internal hardware faultFirmware issueOver-temperature in PCU

What to check

STEP 1

Check battery temperature and ventilation. Power cycle the battery (follow Enphase power-down sequence)

STEP 2

Check firmware version in Enlighten. Update if available

Escalate if

Fault persists after power cycle and firmware is current — hardware fault, escalate to Enphase support with serial number

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More Enphase fault codes

ACVOOR

AC Voltage Out of Range

ACFOOR

AC Frequency Out of Range

DC Res Low

DC Resistance Low (Ground Fault / GFDI)

DC Too Low

DC Input Voltage Too Low

DC Too High

DC Input Voltage Too High