Garage door won't close, or opens again

• It won't start closing at all, or the display shows a beam signal: the safety beams. See beams.
• It starts closing, then stops and goes back up: it's meeting resistance, or something breaks the beams on the way down. See reversing.
• It closes most of the way and stops short, or leaves a gap: the closed position, or something on the floor. See not fully closed.
• A light flashes and nothing happens: an error code or a lock-out. See flashing lights.
• The wall button closes it, the remote doesn't: the remote. See remotes that don't work.

Most garage doors have a pair of safety beams low across the opening, and a door won't close while they're interrupted. Centurion's SDO4 shows E1 when its beams are active, and ET's DC Blue Advanced shows b on its display. Both makers tie auto-close to the beams too: Centurion's SDO4 needs beams fitted for auto-close, and on the DC Blue Advanced, switching auto-close on turns beam mode on.

What you can check, safely:

• Anything in the beam: a box, a bin, a bicycle, a mop leaning in the doorway, a car parked a little too far forward.
• Dirty or webbed lenses, wiped gently with a soft, dry cloth.
• A beam knocked out of line by a car, a ball or a broom. Don't force it; note it and tell us.

A technician lines beams up properly. On Centurion's Photon SMART beams, for example, an alignment mode makes the receiver's light stay on when the beams line up, and go off when they don't.

A door that reverses on its way down is doing what it's designed to do when it meets something. There are two ways that happens:

• Something breaks the beams as it closes. On Centurion's RDO II roll-up motor, for example, the door reverses if the beam is broken while it closes. Look for anything that swings or moves into the doorway, including a plant or a hanging cable.
• It feels resistance. The motor senses the extra effort and reverses. That can be something in the tracks, a roller out of its track, or a door that has become heavy because a spring has weakened or broken. Centurion's SDO4 reports these as E6 (collision), E5 (the door too heavy for the force setting) or E3 (the door out of balance).

Don't be tempted to have the sensitivity turned right down to make it close. Centurion's SDO4 learns its safety force as it learns the door's limits, from F1, the most sensitive, to F5, the least, and warns that at the maximum setting the door is dangerous without beams. A door that needs that much force needs repairing first.

• Centurion SDO4: the courtesy light triple-flashes whenever there's an error, and the display shows the code: E1 beams, E3 balance, E4 run time, E5 force, E6 collision, E7 power, Lb a low battery.
• ET DC Blue Advanced: an H on the display, rapid beeps and a flashing light mean holiday lock-out is on, and the door won't move until it's switched off from the remote.

Our model pages list every code: Centurion SDO4 and ET DC Blue Advanced.

• Something on the floor where the door lands: a stone, leaves, a door stop. The motor treats it as an obstruction.
• The closed position needs adjusting. Floors settle and doors wear. On an SDO4 the closed position can be fine-tuned in 3 mm steps, a quick job for a technician.
• The door is binding near the bottom of its travel: a bent track, a dropped panel or a dry roller.

A small gap at the bottom matters more than it looks: it lets in rain, leaves and rodents, and it may stop the door locking.

Once the door closes again, check that it still stops for things it should. Centurion's SDO4 SMART manual asks that the door stop and reverse when it closes onto a solid object 40 mm high, checked monthly. Keep everyone clear, lay a flat piece of timber in the doorway and close the door onto it. If it presses down and stays there, stop using the motor and call us.

Call us when the beams are clear but the door still won't close, when it reverses with nothing in its way, when the display shows a code you can't clear, or when a spring or cable looks damaged. Never touch the springs or cables yourself. A door stuck open at night leaves the house open; the 24/7 emergency repairs across Gauteng cover exactly that, and our guide to opening a garage door by hand explains how to close and secure it in the meantime.

On the job card, give the motor's make, what the door does, and any code or light you see; tick "It's urgent" if it's stuck open. Same-day repairs are offered when the day allows, and every repair comes with our six-month guarantee on our repairs. No call-out fee when we do the work. If no work is done, a R650 call-out fee applies.