!!
critical Renogy

Error Code E4

Load short circuit detected.

? What Causes This

Fault in the load connection causing a direct path for current flow with low resistance.

How to Fix It

  1. Disconnect any connected devices and check for damaged wiring or connectors.
  2. Reconnect components or replace faulty ones.

Source: page 52 of the official manual

From the manual

Manual page 52 — Renogy error E4

This error code appears in:

Renogy Rover 40a