37

RI Charge Error

Fronius · Perfect Charging

What does 37 mean?

An error occurred during the RI (Internal Resistance) charging process. This specialized charging method monitors battery internal resistance, and a fault indicates a significant deviation from expected behavior or a measurement issue with this diagnostic cycle.

Common Causes

  • A significant and unexpected change or instability in the battery's internal resistance during the RI charge measurement.
  • Malfunction in the charger's dedicated RI measurement circuit or its associated sensors.
  • The battery condition is not suitable for RI charging, or the battery itself is severely degraded.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Assess the battery's internal resistance independently using a dedicated battery diagnostic tool to confirm its health.

  2. 2

    Consult the charger's specific manual for troubleshooting steps related to RI charging diagnostics.

  3. 3

    Verify the charger's RI charging parameters and settings to ensure they are appropriate for the connected battery type.

Browse all codes in this manual (61)
Verified technical data. Last updated: March 2026

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