Fitting a new battery.

Southern Star · 29th January 2022, 16:21

Time for a new starter battery soon I think (although if I can get through the next month or two I might be able to put it off until September as my car traditionally goes on SORN between Easter and September when I go away narrowboating). I could do with delaying it as I've spent over £800 on it in the last month.

I've replaced batteries in the past without issue but I'm getting the idea that I read somewhere that after removing the old battery you are supposed to hold the battery cable terminals together for 30 seconds and then wait 30 minutes before connecting the new battery. I've never done this, should I?

simondhopkins · 29th January 2022, 16:29

Never done this with any of my Rovers, 3 75s, 3 600s, 1 400, and other makes too. Just make sure the car keys are in your pocket when you connect the new battery, had a ford focus lock its doors after I connected the battery.

29th January 2022, 16:42

Put a new battery in mine a couple of weeks ago with no issues. Straight swap, old one out and new one in.

FLYING BANANA · 29th January 2022, 17:12

Done mine on Banana. Old one out and the new one straight in. It had to be easy for me to do it as I’m not normally technically minded.

KeithA · 29th January 2022, 17:20

Likewise never had to do so and have changed on all 3 I have owned. Neg cable off first and on last.

MSS · 29th January 2022, 18:27

A lot of modern cars require a 30 minute or so of battery disconnect for a power reset to take effect. Many actually require the BMS to be provided information on the new battery so that it can re-calibrate itself and optimally maintain the new battery.

With our cars, if all you wish to do is to swap out the battery, there is no need for a waiting period.

Mogodon · 30th January 2022, 10:43

What a bleeding con, having to get a main dealer to supply and code a new battery to your modern car at their part costs and labour rates, along with the coding cost !!!!!!

MSS · 30th January 2022, 16:00

Quote:

Originally Posted by Mogodon

What a bleeding con, having to get a main dealer to supply and code a new battery to your modern car at their part costs and labour rates, along with the coding cost !!!!!!

In a word, no!

Wait until I post my thread on my new diagnostic toy later this evening.

Actually, let's deal with it here. The Battery Management System in our XF periodically partially discharges the battery and then recharges in order to test the battery's condition. This allows it to optimize the charging as well as inform the driver if an excessive load is placed whilst the engine is switched off e.g. the 825W 17-speaker audio system.

There is nothing to stop someone just replacing the battery - with systems such as in the Jaguar, the BMS will catch up at some stage. Alternatively, good dedicated diagnostic scanners will allow the user to reset the BMS.

It's not really a huge deal at the end of the day as personally, I would encourage drivers to invest in the right tools and knowledge or pay people with the knowledge and tools to maintain their cars. These days a local independent that does not have a decent diagnostic scanner with maintenance functions is not worth using for a modern car.

Southern Star · 30th January 2022, 16:42

Out of interest, Halfords want £16 to fit the battery. Last week they wanted £6 to fit a pair of windscreen wipers. Obviously they had to carry on wanting but I'm in the wrong job!

MSS · 30th January 2022, 16:45

Quote:

Originally Posted by Southern Star

Out of interest, Halfords want £16 to fit the battery. Last week they wanted £6 to fit a pair of windscreen wipers. Obviously they had to carry on wanting but I'm in the wrong job!

So they are saying the battery replacement will take 15 minutes and the wiper change about 5 mins.

You cannot really complain about that!

29th January 2022, 16:21	#1
Southern Star Loves to post Rover 75 CTDi Contemporary SE Join Date: Jul 2013 Location: Stretton-under-Fosse, Warwickshire. Posts: 358 Thanks: 54 Thanked 134 Times in 83 Posts	Fitting a new battery. Time for a new starter battery soon I think (although if I can get through the next month or two I might be able to put it off until September as my car traditionally goes on SORN between Easter and September when I go away narrowboating). I could do with delaying it as I've spent over £800 on it in the last month. I've replaced batteries in the past without issue but I'm getting the idea that I read somewhere that after removing the old battery you are supposed to hold the battery cable terminals together for 30 seconds and then wait 30 minutes before connecting the new battery. I've never done this, should I?

29th January 2022, 17:12	#4
FLYING BANANA Moderator/Club Shop MG ZT 1.8t+. No.3 of 4 in Sunspot Yellow & Ford Fiesta in Black. Join Date: Aug 2010 Location: Rattler Farm Posts: 22,560 Thanks: 9,270 Thanked 15,645 Times in 6,806 Posts	Done mine on Banana. Old one out and the new one straight in. It had to be easy for me to do it as I’m not normally technically minded. __________________ 233,431. That’s our second meet done, no.3 next weekend. onen hag oll

29th January 2022, 17:20	#5
KeithA Loves to post Rover 75 Conny Tourer Auto Join Date: Mar 2016 Location: Essex Posts: 347 Thanks: 75 Thanked 94 Times in 71 Posts	Likewise never had to do so and have changed on all 3 I have owned. Neg cable off first and on last. __________________ 2003 Tourer, Connoisseur Auto

29th January 2022, 18:27	#6
MSS This is my second home Rover 75CDT, Jaguar XF-S 3.0V6, V'xhall Omega V6 Estate, Twintop 1.8VVT, Astra Estate and Corsa 1.2 Join Date: Dec 2007 Location: Suffolk Posts: 7,084 Thanks: 283 Thanked 624 Times in 440 Posts	A lot of modern cars require a 30 minute or so of battery disconnect for a power reset to take effect. Many actually require the BMS to be provided information on the new battery so that it can re-calibrate itself and optimally maintain the new battery. With our cars, if all you wish to do is to swap out the battery, there is no need for a waiting period. __________________ Member of the Peasant Underdog Class, Grade 1

30th January 2022, 10:43	#7
Mogodon Gets stuck in MG ZT 135+ Diesel Auto Mk2. Nisan Micra 1.4 SVE Auto. Join Date: Apr 2015 Location: Wellingborough, Northamptonshire. Posts: 834 Thanks: 196 Thanked 198 Times in 84 Posts	What a bleeding con, having to get a main dealer to supply and code a new battery to your modern car at their part costs and labour rates, along with the coding cost !!!!!! __________________ Plenum spyhole mod. Powerflow backbox. 11 spoke alloys repainted Black Sparkle. Black Expansion tank. Drivers side cup holder. PPD carpeted heater box sides. Illuminated sun visors, PPD Door reflectors. PPD Seatbelt lower mount bolt covers. PPD Drivers grab handle. Cubby rechargeable torch and power socket. FBH retro-fitted. FBH engine pre-heater mod done. Electric rear Sunblind. Tow bar. Flip key. MGR towing mirrors and Saloon roof bars. Hand Built in Birmingham

29th January 2022, 16:29	#2
simondhopkins Loves to post Vauxhall Vectra C Join Date: Jul 2016 Location: Burnley Posts: 445 Thanks: 179 Thanked 88 Times in 62 Posts	Never done this with any of my Rovers, 3 75s, 3 600s, 1 400, and other makes too. Just make sure the car keys are in your pocket when you connect the new battery, had a ford focus lock its doors after I connected the battery.

29th January 2022, 16:42	#3
Bazzateer Guest Posts: n/a	Put a new battery in mine a couple of weeks ago with no issues. Straight swap, old one out and new one in.

30th January 2022, 16:42	#9
Southern Star Loves to post Rover 75 CTDi Contemporary SE Join Date: Jul 2013 Location: Stretton-under-Fosse, Warwickshire. Posts: 358 Thanks: 54 Thanked 134 Times in 83 Posts	Out of interest, Halfords want £16 to fit the battery. Last week they wanted £6 to fit a pair of windscreen wipers. Obviously they had to carry on wanting but I'm in the wrong job!