These instructions apply to the Honda Accord Mk7 (CL/CM) 2003-2008.
For other models, please choose your vehicle here.
Disconnecting the battery on a seventh-generation Honda Accord (the CL/CM European saloon and Tourer, 2003–2008, sold in North America as the Acura TSX) is straightforward, but it wipes several volatile memories. Have your radio code ready before you start, and expect to reset the clock and re-initialise the electric windows afterwards.
Before you start
- Find your audio system security (radio) code and keep it to hand — the head unit locks the moment power is lost.
- Switch the ignition fully off, turn off all electrical loads, and remove the key.
- The 12 V battery sits in the engine compartment; have the correct spanner for the terminal clamp nuts before you open the bonnet.
Disconnecting and Reconnecting — Step by Step
- With the ignition off and the key removed, wait at least three minutes before touching the terminals if any work will take place near airbags or seat-belt pretensioners, so the pyrotechnic circuits fully discharge.
- Loosen the clamp on the negative (−) terminal first and lift the lead clear of the post, tucking it aside so it cannot spring back onto the battery.
- Loosen and remove the positive (+) lead next.
- Carry out whatever work needed the battery isolated — fitting a new battery, bodywork, or an electrical repair.
- Reconnect the positive (+) lead first and seat it on the post.
- Reconnect the negative (−) lead last.
- Tighten both clamp nuts so the leads are firm and cannot move, then close the bonnet.
After Reconnecting — What to Restore
Losing power clears the Accord’s volatile settings, so put them back before you drive off:
- Reset the date and time (set the clock).
- Re-enter the radio anti-theft code to unlock the audio system (and the navigation code on cars with factory sat-nav).
- Re-initialise the power windows so the one-touch auto up/down function works again.
Frequently Asked Questions
Which battery terminal do I disconnect first on the Accord?
Always the negative (−) terminal first. On reconnection you reverse the order: positive (+) first, then negative (−) last. This keeps a dropped spanner from shorting a live post to the bodywork.
Will I lose my radio when I disconnect the battery?
Yes. The head unit locks and asks for its security code once power returns, so make sure you have that code before you disconnect. You will also need to reset the clock afterwards.
Where is the battery on a 2003–2008 Accord?
In the engine compartment. Open the bonnet and you will find the 12 V battery with its clamped positive and negative terminals ready to release.
Do I need to keep power to the car while the battery is off?
No, it is not essential. A memory-saver plugged into the accessory socket can preserve the radio code, clock and window settings, but if you do not use one you simply restore those items by hand afterwards.
If the battery went flat because a warning light was already showing, read the stored fault first — our sister site autodtcs.com explains what the OBD-II trouble codes behind those lights actually mean.
Independent guide — not affiliated with Honda. Always follow your official service manual and safety precautions. Read our full disclaimer.