Gliderol opener displays E9; door moves erratically, reversing without hitting an obstruction, or travel distance changes each cycle.

Safety first: Isolate power before accessing the motor and encoder. Avoid touching live terminals.

Steps to correct encoder issues:

• 1. Inspect encoder wiring: Locate the small multi‑core cable from the motor to the control board. Ensure the plug is fully seated and wires are not pinched or cut.
• 2. Check encoder disc/magnet: On some Gliderol models, a slotted disc or magnet ring is attached to the motor shaft. Confirm it is not loose, cracked, or contaminated with grease. Clean gently with a dry cloth.
• 3. Secure cable routing: Keep encoder wiring away from mains cables and motor leads to reduce electrical noise. Use cable ties to secure.
• 4. Relearn travel: After reconnecting, perform a full travel/limit learn cycle as per the Gliderol manual so the controller recalibrates position.

If E9 persists, the encoder sensor or the control board’s input circuit is likely defective. Replacement of the encoder assembly or entire motor/board may be required.