LG CordZero: Replacing the Power Button Switch

Bottom line: An LG CordZero power button that only works sometimes has a worn tactile micro-switch, and it is a fixable, advanced 45-minute job. The two tricky parts are the hidden Torx T8 screws under the grip strips and the fragile ZIF ribbon connector.

Remove the battery completely. Discharge residual power by pressing the power button 5 times after battery removal. Unplug from charging station.

Tools and parts#

Step by step#

1. Confirm the switch is the problem#

Fit a fully charged battery and try each power mode. If some buttons work but not others, that mode's switch has failed; if nothing responds at all, look instead at the battery contacts or the main PCB before opening the button assembly.

2. Remove the external components#

Pull the battery pack, the dust bin with its Kompressor assembly, the extension wand, and the HEPA exhaust filter so you have the bare body housing. Remove the wall bracket if it is still attached and set everything aside.

3. Open the main body housing#

The CordZero A9 body is a two-piece clamshell. Peel back the rubber grip strips to reveal the hidden Torx T8 screws (two per side), then remove two more on the bottom and two by the rear exhaust vent — eight T8 screws total. Work the seam with the spudger to release the internal snap clips, starting at the bottom.

4. Locate the power button PCB#

The button sub-assembly is a small PCB at the top of the body, in the housing half with the external button, with the tactile switch soldered to it. It joins the main board by a ribbon cable — release it by lifting the ZIF connector lock bar on the main-board end and sliding the ribbon free.

5. Remove the button PCB#

The board is held by one or two small Phillips screws or by molded snap posts, depending on the revision. Remove the screws or gently unclip it, noting that the switch faces the housing's button hole and the ribbon routes through a channel.

6. Replace the switch or the whole PCB#

The easier path is a full PCB swap: drop the new assembly in, route the ribbon through its channel, secure it, and reconnect the ribbon to the main board. If you are replacing only the switch, desolder the worn micro-switch and solder in a matching 6mm tactile part of the same height.

7. Reassemble and test#

Slide the ribbon fully into the ZIF connector and flip the lock bar down, then close the housing halves with no cable pinched in the seam. Refit all eight T8 screws and the grip strips, install the battery, and confirm every button press gives an immediate, consistent response.

8. Verify long-term reliability#

Over the next week, watch that the button fires cleanly on a light tap every time, without needing extra presses or a specific angle. If intermittent behavior comes back quickly, the ribbon connection is marginal — reopen and reseat it.

If it still misbehaves#

• Works open but not closed: the external button stem or a loose rubber cap is not aligned with the switch — reseat the cap in its molded recess.
• Turns on randomly: the new switch actuates too easily; use one with higher actuation force (160-260gf is typical for LG) or add a thin foam pad.
• Light works but the motor does not: the press is registering, so the fault is a separate motor-control issue on the main PCB.

When to call a pro#

A damaged ZIF connector needs a new one soldered on, which is delicate work. See our vacuum repair cost guide or book a same-day repair.