These instructions apply to the MG HS Mk1 2019-present. For other models, please choose your vehicle here.
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When your MG HS (2019–present) only locks from close range, the key battery is flat. It’s a quick swap with no reprogramming.
The Cell You Need
The HS remote takes a single CR2032 3 V coin cell. Buy one before you open the key.
Opening the Key
- Press the button and pull out the mechanical key blade.
- Separate the case halves with a flat-bladed screwdriver in the slot.
- Remove the old CR2032 — it sits with the positive (+) side facing down.
- Fit the new cell the same way, clip the case together and refit the blade.
After the Swap
Start the car once to confirm. A battery change keeps the existing pairing — no reprogramming needed.
Frequently Asked Questions
What battery does an MG HS key take?
A single CR2032 coin cell, fitted positive-side down.
Do I need to reprogram after changing it?
No — the key keeps its pairing through a battery change.
My key still won’t work — now what?
Use the blade to unlock the driver’s door, and hold the fob against the start button to start on the transponder, then check the cell is seated correctly.
Which way up does the cell go?
Positive (+) facing down, as the original was fitted.
If the car won’t respond at all, the 12 V battery may be flat — see our HS battery guide. For a stored code, look it up on autodtcs.com.
Disclaimer: The information on this page is provided for general guidance only. Always follow your official service manual and safety precautions when working on your vehicle. We are not responsible for errors, omissions, or any damage resulting from the use of this information.
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