Tools you need for battery on a 2013-2017 Honda Accord
Easy · 20-40 minutes · Updated 2026-09-28
Must-have tools
10 mm socket, 1/4 in drive
Ratchet with 6-10 in extension
Battery terminal brush/cleaner
Group 51R battery
Battery replacement on the 9th-gen Accord is one of the easiest jobs on the car. The battery sits in the driver's-side front corner, everything on it is 10 mm, and there is no battery registration or dealer coding involved. The only mildly annoying part is the hold-down bolt, which is down beside the tray and wants a 1/4 in ratchet with a 6-10 in extension rather than a stubby wrench.
The main thing people get wrong is the battery group size. The Accord takes a 51R, and the R matters: a plain 51 has the posts reversed and the cables will not reach. The second thing is skipping the idle relearn, then complaining about a rough or hunting idle for a week. Let it idle 10 minutes in Park after reconnecting and it settles down.
Which store near you has these? WhatWrench checks the shelves at your nearest auto parts and hardware stores.Find them near me
Complete tool and parts list
Item
Type
Safety glasses
Protects eyes from battery acid and corrosion dust.
No difference in tool sizes between the 2.4 L K24W four-cylinder and the 3.5 L J35Y V6; both use a Group 51R battery, 10 mm terminal bolts and a 10 mm hold-down bolt. Hybrid Accords of this era have a separate 12V accessory battery and a high-voltage pack, and should not be treated as the same job.
Torque specs
Battery terminal clamp bolts (10 mm)
About 4 ft-lb (5 Nm) - snug only, verify in the service manual
Battery hold-down bracket bolt (10 mm)
About 6 ft-lb (8 Nm) - verify in the service manual
How the job goes
Park on level ground, turn the ignition fully off, remove the key, and let the car sit a minute so modules go to sleep. Open the hood and prop it.
If you want to keep radio presets and learned values, plug a memory saver into the OBD-II port under the driver's dash or the accessory socket (accessory socket only works if it is hot with the key out).
Locate the battery in the driver's-side front corner, behind the headlight and next to the underhood fuse box. Lift off the red positive terminal cover if fitted.
Loosen the negative (black, marked -) terminal pinch bolt with the 10 mm socket and lift the clamp off the post. Tuck it aside so it cannot fall back onto the post.
Loosen and remove the positive (red, +) clamp the same way.
Find the hold-down bracket that clamps the lip of the battery case. Using the 10 mm socket on a 6-10 in extension, back the bolt out of the J-hook. Keep the bolt, bracket and hook together so the hook does not drop into the tray.
Lift the battery straight up and out. It is a small 51R but still awkward and heavy; use a carry strap and keep it level.
Clean the tray with baking soda solution or battery cleaner, then dry it. Wire-brush any white or green corrosion off the tray, the hold-down hardware and the inside of both cable clamps.
Check that the new 51R has the positive post on the same side as the old one, peel off any shipping caps, and set it into the tray squarely with the posts facing the same direction as before.
Refit the J-hook into the tray slot, seat the bracket on the battery lip, and tighten the bolt until the battery cannot rock. Do not crush the case.
Connect the positive cable first and snug the pinch bolt, then the negative cable. Try to twist each clamp by hand; it should not move.
Fit felt anti-corrosion washers or spray the terminals, then refit the positive terminal cover.
Start the engine. Let it idle in Park, no load, for about 10 minutes so the ECM relearns idle. Do not blip the throttle.
Reset the clock, radio presets and Bluetooth pairing if you did not use a memory saver. Cycle each power window fully down and fully up and hold the switch a second at the top to restore auto-up.
Check resting voltage with the engine off (12.5-12.7 V) and charging voltage at idle (13.5-14.7 V). Return the old battery for the core deposit.
Watch out
Always disconnect negative first and reconnect it last. A wrench bridging the positive post and the body will weld itself and can burst the battery.
Do not let the tools or the battery contact the hood latch support or fender edge while carrying it out; short circuits here can blow the main fuse.
Hydrogen gas around a battery is explosive. No smoking, no sparks, and do not lean over the battery while making the final connection.
Do not overtighten the hold-down; a cracked case will leak acid onto the tray and frame rail.
After power loss the audio and navigation may prompt for a moment while it reinitializes, and the tire pressure monitor may need a drive cycle to reset. Both are normal.
This generation does not require battery registration or coding, but a memory saver saves you time on radio and idle relearn.
If the car has been sitting with a dead battery, check for a parasitic drain before assuming the battery was just old.
The 10 mm sizes for the terminals and hold-down bolt and the Group 51R fitment are solid across 2013-2017 Accord sedans and coupes with both the K24W and J35Y; confirm your group size against the label on the old battery and check torque values in the factory service manual.
Frequently asked
What size battery does a 2013-2017 Honda Accord take?
Group 51R, typically rated around 410-500 CCA. The R is critical: it puts the positive terminal on the correct side for the Accord's cable routing. AGM 51R batteries fit fine and last longer.
Do I need to reprogram or register the battery on a 9th-gen Accord?
No. Honda does not use battery monitoring that requires registration on this generation, so you can fit a new battery and drive. You will just need to reset the clock, radio presets and window auto-up, and let the engine idle about 10 minutes to relearn idle.
What socket do I need for the Accord battery hold-down?
A 10 mm socket on a 1/4 in ratchet with a 6-10 in extension. The bolt threads into a J-hook low beside the tray and is hard to reach with a wrench alone.
Why is my Accord idling rough after a battery change?
Disconnecting the battery wipes the ECM's learned idle values. Let it idle in Park with no accessories for around 10 minutes without touching the throttle, then drive normally; it should be smooth within a drive cycle or two.