Powerwall 3 is Displaying 0A for a Connected String

One string has a DC input of 0V despite having a string of panels connected

Warning IconA warning icon, calling your attention to a possibly risky situation
Warning
Turn the Powerwall 3 Enable switch OFF to de-energize the system before terminating, removing, or modifying any conductors inside Powerwall 3. Confirm lack of voltage at the AC and PV terminals before proceeding.

Symptoms

On the landing page, solar production is lower than expected. On the Powerwall 3 Device page, a connected DC string is grayed out and the solar production for that string is 0A.

Figure 1. Powerwall 3 System Displaying Incorrect Number of Strings

Steps to Troubleshoot

  1. Confirm the string is connected to Powerwall 3.
  2. Confirm MCIs have been connected in the string.
    Informational PurposesAn informational icon, calling your attention
    Note
    If the system detects MCIs connected in one string but not all, the system will fail self-tests and the string(s) without MCIs will display 0V until MCIs are detected in all strings.
  3. Perform a Powerwall 3 MPPT diode test:
    1. Set the multimeter to Diode test mode.
    2. Disconnect the PV conductors from the Powerwall 3 PV connector.
    3. Test each MPPT in the Powerwall 3 PV connector:
      1. Place the multimeter positive (red) test probe in a PV - terminal.
      2. Place the multimeter negative (black) test probe in the corresponding PV + terminal.
        Figure 2. Powerwall 3 P/N 1707000-11-L and Higher or 1707000-21-L and Higher
        Figure 3. All Other Powerwall 3 Units
      3. Confirm the multimeter reading is between 0.3 and 0.55 V.
      4. Repeat this sequence for each pair of terminals. If an MPPT displays a reading outside the 0.3 to 0.55 V range, this indicates a failed MPPT. To proceed:
        • Move the string to an MPPT that has not failed the diode test.
        • If there are no available MPPTs, contact Tesla Support for guidance to return the Powerwall 3.
  4. See DC Voltage Test (Completed String and Polarity) to confirm string polarity is correct.
  5. See Determine True String VOC to identify possible stringing issues.
  6. If the issue is not resolved by troubleshooting the strings, the system may have a faulty MCI. Perform the troubleshooting steps in MCI Diode Test and Resistance Test (MCI Health Tests) to identify the faulty MCI(s).
  7. If the issue persists, contact Tesla Support.