UK & Ireland S2000 Community Discussions related to the S2000, its ownership and enthusiasm for it in the UK and Ireland. Including FAQs, and technical questions.

Battery Change Advice

 
Old 05-09-2019, 02:35 AM
  #1  
Registered User
Thread Starter
 
Join Date: Sep 2016
Posts: 114
Received 8 Likes on 7 Posts
Question Battery Change Advice

Hi,

I'm about to change the battery on my S2000.

To avoid all the hassle with losing fuel trims, ECU recalibration etc can I simply leave a battery charger connected to the battery leads to keep +12v on the car while I change the battery over? Then, simply remove them once the terminal have been re-tightened on the new battery?

Are there any issues I need to be aware of putting a battery charger directly to the leads without the battery connected in the system?

Thanks for any advice.
ValveBounce is offline  
Old 05-09-2019, 03:19 AM
  #2  
 
Join Date: Jan 2016
Location: Seaton Devon
Posts: 49
Likes: 0
Received 1 Like on 1 Post
Default

Originally Posted by ValveBounce View Post
Hi,

I'm about to change the battery on my S2000.

To avoid all the hassle with losing fuel trims, ECU recalibration etc can I simply leave a battery charger connected to the battery leads to keep +12v on the car while I change the battery over? Then, simply remove them once the terminal have been re-tightened on the new battery?

Are there any issues I need to be aware of putting a battery charger directly to the leads without the battery connected in the system?

Thanks for any advice.
Not really a good idea as the battery acts as a buffer against any spikes the battery charger may give out. If you get a voltage surge it will damage electronic parts like the ECU. Not a good idea.

Normally the ECU will relearn all settings very quickly, so if you change the battery normally, which takes about 10 minutes at the most, all should be OK.
seatonsurfer is offline  
Old 05-09-2019, 03:26 AM
  #3  
 
flanders's Avatar
 
Join Date: Aug 2013
Location: Sweden
Posts: 2,743
Received 133 Likes on 130 Posts
Default

What kind of charger do you got? Some models has a supply feature for cases just like this.
flanders is online now  
Old 05-09-2019, 03:29 AM
  #4  
 
richmc's Avatar
 
Join Date: May 2010
Location: Costa del Cornwall
Posts: 7,930
Received 45 Likes on 43 Posts
Default

Originally Posted by ValveBounce View Post
Hi,

I'm about to change the battery on my S2000.

To avoid all the hassle with losing fuel trims, ECU recalibration etc can I simply leave a battery charger connected to the battery leads to keep +12v on the car while I change the battery over? Then, simply remove them once the terminal have been re-tightened on the new battery?

Are there any issues I need to be aware of putting a battery charger directly to the leads without the battery connected in the system?

Thanks for any advice.
You won't lose fuel trims, just the radio code, I changed my battery a long time ago by jump leading the old and new one together, before I had the code. A modern smart charger will detect there is no battery and switch off. Anyway unless you have an exotic ECU and are non NA, it just takes a drive to reprogram it anyway.
richmc is offline  
Old 05-09-2019, 08:36 AM
  #5  
Registered User
Thread Starter
 
Join Date: Sep 2016
Posts: 114
Received 8 Likes on 7 Posts
Default

Thank you for your replies.

The battery charger is not new/modern. It's a very simple device with a switch that selects 6v or 12v and that's about it.

From all your suggestions I think the best plan is just to jump a battery onto the battery leads while I swap the batteries over. Hopefully that will work but if not the car will just be a bit lumpy until the ECU has sorted itself out. It's the standard Honda OEM ECU on a regular NA engine, nothing fancy.
ValveBounce is offline  
Old 05-09-2019, 11:30 PM
  #6  
 
flanders's Avatar
 
Join Date: Aug 2013
Location: Sweden
Posts: 2,743
Received 133 Likes on 130 Posts
Default

It will most likely work fine with that charger connected during the swap, I would just check the open circuit voltage and make sure it's not too high before using it.
flanders is online now  
Old 05-09-2019, 11:51 PM
  #7  
UK Moderator
 
Join Date: Jan 2004
Location: Herts
Posts: 23,919
Received 90 Likes on 87 Posts
Default

Originally Posted by ValveBounce View Post
Thank you for your replies.

The battery charger is not new/modern. It's a very simple device with a switch that selects 6v or 12v and that's about it.

From all your suggestions I think the best plan is just to jump a battery onto the battery leads while I swap the batteries over. Hopefully that will work but if not the car will just be a bit lumpy until the ECU has sorted itself out. It's the standard Honda OEM ECU on a regular NA engine, nothing fancy.
I disconnect my battery each winter while the car is SORN. There are no problems at all with lumpy idle or anything else after reconnection. All that's required is a clock and radio reset.
lovegroova is offline  
Old 05-10-2019, 02:36 AM
  #8  
 
Chuck S's Avatar
 
Join Date: Jul 2014
Location: Chesterfield VA
Posts: 7,200
Received 259 Likes on 246 Posts
Default

Do not mess with a battery charger here, dealers and other shops change batteries daily without losing ECU settings. You will need to reset the clock and radio. Notice that all your mileage data on the dash stays the same as it's in permanent memory as is the bulk of all data in the car. The radio losing settings is an anti-theft scheme.

-- Chuck
Chuck S is offline  
Old 05-10-2019, 05:10 AM
  #9  
 
Daytona-Dave's Avatar
 
Join Date: Sep 2012
Posts: 2,844
Received 49 Likes on 36 Posts
Default

AS above just swap the battery and stop piss balling about with something that may create a spike if you arc it out or slip, you will only need to reset the radio code,
after you start it let it idle till warm and the fan has cut in a few times to relearn the idle and your good to go, it actually does them good to reset once in a while you are worrying over nothing but have the potential to cause problems by going down your route,
Daytona-Dave is offline  
The following 2 users liked this post by Daytona-Dave:
Booti (05-10-2019), RobinA3 (05-10-2019)
Old 05-13-2019, 10:02 AM
  #10  
 
Join Date: Sep 2009
Posts: 161
Received 1 Like on 1 Post
Default

Tried this battery charger trick so I didn't have to re-code the radio when I changed the battery, however, knocked one wire off and thought "bugger" but the radio code still held, phew!! great relief.
so maybe there is a time lag built in between disconnection and re-connection of battery voltage
?
eriktheredd is offline  

Quick Reply: Battery Change Advice


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands