Automatic gates can open and fail to close due to mechanical factors (such as a hinge that is poorly lubricated) or electrical factors. You can get the problem fixed without calling professionals to help you. However, fixing the problem depends on correctly diagnosing what has caused the malfunction. This article discusses some electrical factors that make an automatic gate fail to close.
A "Hold Open" Command
Automatic gates come with several gate openers that different members of the family use to get in and out of the gate. It is possible that one member of the family may enter a "hold open" command on their gate opener without your knowledge. When you enter the gate and try to enter a command to close it, the "hold open" command entered earlier on by another person will override your "close" command, so the gate will stay open. To solve this problem, ask other family members who have gate openers to check if they entered the "hold open" command either deliberately or accidentally. Once the opener that has that command is identified, all you have to do is to cancel that command and the gate will slide shut.
Blocked Photo Eyes
Photo eyes are electronic sensors that emit rays that detect when an object passes through the gate and blocks the rays from moving across to the photo (light) sensor on the other side of the gate. If there is dirt on these photo eyes, they will fail in their role so the gate may fail to close since its mechanism will be telling it that there is a barrier (such as a moving car). Solve this problem by cleaning off any dirt that has accumulated on the photo eyes, and they will begin functioning well again.
Discharged Transmitter Batteries
Many reversing edges of automatic gates have transmitters with a battery. That battery may wear out, causing the gate to stop shutting itself. If your gate has this type of transmitter, check the battery using a voltage tester to confirm whether it has worn out or it is still functioning (batteries have a voltage rating on them, so the tester will tell you if it is within the operating range or it is now too low to power the reverse edge). If the battery is worn, replace it. If it is okay, check the terminals of the transmitter for rust and buy a replacement terminal if the terminals have corroded.
Use the information above to help you to troubleshoot the most common electrical causes that make automatic gates fail to close. You will save the money that you would have spent to bring a technician to restore the functioning of that gate.