Ryobi garage door opener will not respond to wall control or remotes; display shows E4.

Safety first: Turn off power to the opener before working on wiring. Use a non-contact voltage tester if available.

• 1. Test power outlet: Plug a lamp or tool into the ceiling outlet used by the Ryobi opener to confirm it has power. If no power, reset the breaker or repair the outlet.
• 2. Check wall control wiring: Remove the wall control from the wall. Inspect the two low-voltage wires for cuts or shorts. At the opener head, verify the wall control wires are connected to the correct terminals (often marked WALL CONTROL or with specific icons).
• 3. Bypass wall control: With power on, briefly short the two wall control terminals at the opener head using an insulated screwdriver. If the door operates, the wall control or its cable is faulty. Replace the wall control or run new low-voltage cable.
• 4. Inspect for shorts: Follow the wall control cable along the wall and ceiling. Look for staples driven through the wire or crushed sections. Repair or replace damaged cable.
• 5. Reset opener: Power cycle the Ryobi opener by unplugging it for 30 seconds and plugging it back in. If E4 remains and bypassing the wall control does not operate the door, the logic board may need replacement.