Disconnect and Reconnect the 12V Battery

The 12V battery on the North American Accord (2008–2012) is in the engine compartment. Disconnecting it clears a few settings — the radio locks and asks for its code — so note that code first.

This is the North American Accord. For the European Accord (CU/CW, 2008–2015) see the European guide.

How to disconnect and reconnect the battery on a Honda Accord (2008–2012)

1. Turn off the ignition and all accessories, and make sure you have the audio security code.
2. Loosen and remove the negative (−) terminal first, then the positive (+).
3. If you will work near the airbags or seat-belt pretensioners, wait a few minutes after disconnecting before touching them.
4. Reconnect in reverse: positive (+) first, then negative (−); tighten both clamps.
5. Switch on and restore the lost items: re-enter the radio code, reset the clock, and re-initialize the power windows.

Always take the negative terminal off first and put it back last, so a slipped tool on the earthed side cannot short the battery through the body. A memory saver in the 12V socket keeps the presets alive but is optional.

After reconnecting, the one-touch auto-up windows usually need re-teaching, and on 2008–2012 cars the TPMS may need re-calibrating once pressures are confirmed.

Frequently asked questions

Will I lose my radio code?

Yes. The audio unit locks and shows ENTER CODE when it loses power. The code is on a card with the car’s paperwork, or a dealer can retrieve it from the unit’s serial number.

Which terminal comes off first?

The negative (−) first, and it goes back on last. Working the grounded side first prevents a short if a tool touches bodywork.

What needs resetting afterward?

The clock, radio code and presets, the power-window auto-up, and often a TPMS re-calibration once the tire pressures are set correctly.