Keypad flashing and not recognising PIN/passcode

Keypad flashing and not recognising PIN/passcode


Alert
Read before you start troubleshooting. 
If the troubleshooting steps in this article do not resolve the issue, we will ask you to provide a few photos and short videos so we can assist you further. You are welcome to capture the necessary images and recordings as you work through the troubleshooting process, which will help us assess the situation more efficiently.
- A short video demonstrating the issue.
-  A screenshots of your lock's battery levels before and after you install new batteries
- A video showing what happens when you power your lock with a USB cable
- Photos of the cables that connects the lock panels
- Take the interior lock panel off the door and take a photo of the tailpiece showing how far the tailpiece extends (only applicable to SDL-T1, SDL-R1, SDL-PP1, and SDL-PP2)
- A zoomed out photo of where the lock is installed
- A screenshot showing the firmware of the lock is up to date

When a smart lock keypad lights up random numbers and refuses to accept valid passcodes, it usually points to a power or connection issue rather than a simple settings problem. Here are the most common causes and what you can check.

Weak or unstable batteries
Low voltage is the most frequent reason for erratic keypad behaviour.
What to do:
- Replace all batteries with brand new, high-quality batteries.
- Do not mix old and new batteries.
- Avoid rechargeable batteries unless the model specifically supports them.

After replacing the batteries, test the keypad again before moving on. If it still doesn't work power up the lock with a USB cable (refer to this article for more info).

Loose or damaged cables
The front keypad connects to the interior panel through a ribbon cable. If that cable is loose, pinched, or partially damaged, the keypad can flash random digits and fail to read passcodes correctly.

What to check:
- Remove the interior panel and reconnect the cables
- Look for visible cuts or creases in the cable.

Slamming the door
Repeatedly slamming the door can loosen internal connections over time. The impact travels through the lock body and may partially dislodge the ribbon/cable that connects the keypad to the motherboard or stress the keypad board.

Encourage gentle closing, especially with fully automatic locks.

Installation issues that strain the motor
Incorrect installation can place unnecessary pressure on the internal motor. Over time, this strain may cause electronics to fail.

For fully automatic models such as SDL-T1, SDL-R1, SDL-PP1, and SDL-PP2, check the following:
- Tailpiece length
The tailpiece must not be too long. If it extends too far, it can press against the internal mechanism and force the motor to work harder than intended. Continuous resistance of this kind may lead to a faulty motherboard.

- Door opening direction setting
The lock must be programmed for the correct door opening direction. If this setting is incorrect, the motor may attempt to operate in the wrong direction. This causes unnecessary strain and can result in a faulty motherboard.

Exposure to direct heat
Prolonged exposure to strong heat sources can raise the internal temperature.
- Direct sunlight for extended periods
- Nearby heaters or heat vents

Consistent exposure to high temperatures may cause the lock to overheat and the electronics to fail.

Exposure to rain, humidity, or salt air
Moisture can affect internal electronic components. If a lock has been exposed to rain, high humidity, or salt spray, moisture may reach the motherboard. This can interfere with the touch sensor and keypad board.

Signs include:
- Random lighting without touch
- Intermittent response
- Corrosion in the battery compartment

If moisture has entered the front panel, the front panel may need to be replaced.

Firmware not up to date
Firmware updates for smart locks are crucial software improvements that fix bugs, boost security, enhance performance (like battery life, motor control, connectivity), and add new features, ensuring the lock stays modern and reliable without needing hardware replacement, usually installed through the lock's app over Bluetooth while the phone is nearby. Performing a bulky firmware update could also result in batteries to drain. Therefore always install brand new batteries after a firmware update. 



Your smart lock may be stuck
Reset the lock and install brand new batteries. Follow the instructions in the article to reset the lock and restore normal operation.

Touchscreen or keypad board fault
If all the above are fine, the keypad board itself may be faulty.

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