Door stops and reverses shortly after starting to open; opener displays E4 or four flashes; may stall mid‑open and then reverse or stop.

Safety first: Disconnect power before adjusting brackets. Do not attempt to straighten severely bent door sections; they may need replacement.

• Step 1 – Inspect door panels and hinges: Look for bent or cracked panels, loose hinge screws, or twisted hinges that cause the door to bind when opening. Tighten loose screws and replace damaged hinges.
• Step 2 – Check top bracket and opener arm: Inspect the B&D door arm and top door bracket where it attaches to the door. Ensure bolts are tight and the bracket is not pulling away from the door.
• Step 3 – Inspect horizontal tracks: With the door disconnected from the opener, manually open it fully and check that the rollers sit correctly in the horizontal tracks without rubbing or binding. Adjust track brackets if necessary.
• Step 4 – Lubricate rollers and hinges: Apply a light lubricant to metal rollers and hinge pins. Avoid getting lubricant on the belt or chain drive.
• Step 5 – Reset open force and travel: Reconnect the opener and follow the B&D procedure to re‑learn open travel and force. Run a full open/close cycle while observing for any sticking points.
• Step 6 – Persistent E4: If the door moves freely by hand but the opener still reports E4, the motor current sensing or control board may be faulty. Have a technician test the opener and replace the control board or motor if required.