5301 (4300) Backup operation ACCT sensor fault

What does 5301 (4300) mean?

This fault indicates a problem with the ACCT (Alternating Current Current Transformer) sensor circuit during backup operation. It can be caused by an open circuit, a loose ACCT connector, or faulty ACCT wiring.

• ACCT sensor circuit fault.
• Open-circuited IPM (Inverter Power Module) / Loose ACCT connector.
• Faulty ACCT wiring.
• Defective inverter/compressor.

Click steps to track your progress.

1. 1

   Turn off the power to the outdoor unit at the circuit breaker.

2. 2

   Check the connector (CNCT2) on the INV board for proper and secure connection.

3. 3

   Verify that the output wire from the ACCT sensor is properly connected.

4. 4

   Inspect the ACCT wiring for any signs of damage or looseness.

5. 5

   Restore power and observe if the unit resumes operation. If the problem persists, the INV board may need replacement by a technician.