Step 1: Check for door misalignment
Possible causes:
Door not properly closed
Door is misaligned with the frame/strike box
Obstruction in the strike box
Test the Lock: Open the door and lift the inside handle and verify that the deadbolt extends properly.
Result:
Locks properly: The issue is with the door alignment, customer should contact their installer.
Does not lock: Issue may be with the lock — proceed to Step 2.
Step 2: Check lock and installation conditions
Battery Check: Replace with a fresh set of disposable alkaline batteries.
Door Thickness: Ensure the door thickness is 38–60 mm.
< 38 mm: Indicates improper installation. A thin door may have damaged the mortise. Advise replacement via the spare parts website.
> 60 mm: Confirm that the recommended extension kit is installed. If not, advise replacing the mortise and purchasing the appropriate extension kit.
(If within correct thickness and using an extension kit, proceed with the next steps)
Step 3: Inspect the Handle Shaft Springs
**If the customer agrees to uninstall the inside panel:
Verify handle shaft spring installation
Check that the shaft springs are installed correctly.
If the springs are missing
The springs must be installed for proper locking operation.
If the customer no longer has the springs, refer them to the MSL Replacement Parts website to order replacements
If the springs are correctly installed and the issue persists
Replace the inside or outside panel, depending on which handle is unable to lock the door.
Proceed with the Warranty Claim and Technical Escalation process, if applicable.
If the customer does not agree to uninstall the inside panel:
Proceed directly with the Warranty Claim and Technical Escalation process.