Until a couple of years ago, for 16 years, my daily and only car was a 1973 MG Midget so very little electric stuff on it, though it did have interior and boot lights and an alternator (a number of weeks older and it would have been a dynamo) those luxuries weren't on my 1969 Spridget that I used as a daily in the mid-1990s, I never had any battery issues with those cars.

 

I've been charging elderly neighbours' car batteries for decades now and helping those younger that don't know or have forgot so was experienced with this but this needs 'coding' to change the battery was all new to me when my wife got the start/stop Fabia.  This gave me a level of annoyance and inconvenience as I was yet to have a neighbour with a higher level scan tool and had to seek help from a Briskoda member to do the 'coding'.  Thus the learning on this began with the usual level of missing info from VW and I wasn't confident with the info I got from a BMW "technician" (the husband of my wife's boss) who wasn't sure!

 

No problem mate.  For your car, just keep it simple, no need to overcomplicate or overthink on this.  As has been mentioned, give it a good charge.  If it's still a bit sluggish or loses charge quickly, just chuck another on and don't worry.  My son's battery was around 8 years' old when it failed (the original).  I tried recovering it but my smart charger gave me an error saying the charger voltage didn't match the battery voltage, so it was FUBAR.

 

As was confirmed above, a voltage over 12v would indicate the battery is decent (see post above).

1 hour ago, beezera10 said:

I tried recovering it but my smart charger gave me an error saying the charger voltage didn't match the battery voltage, so it was FUBAR.

Not always the case, obviously I don't know with your son's battery but a lot of these so-called "smart" chargers ain't that smart (same as "smart" phones) and they need to see certain levels of voltage or they think the battery is "dead" and unrecoverable.  Some of these voltages can be quite high considering, some chargers actually bother to tell you how low they go in their instructions but there are ways of getting around the "smart" charger to get them to do their work.  8 years isn't necessarily that old for a battery but it does depend on a lot of variables including the car and the owner/driver(s).

 

I'm with you for SteveTheElder's battery, if there's no battery monitoring and start/stop I'd take the battery off the car and fully charge it - or charge it on the car but again fully, if I hadn't the time available and/or needed to use the car to fully charge it in one go then I'd fully charge it in the second go as soon as possible after the first go.  Low and slow to fully charged is what's required for best results and longer reliable battery life.  Any recharging is better than none but quick (higher amps) partial recharging isn't best.

 

On 15/08/2024 at 21:01, nta16 said:

Let us know how you get on whether trying recharging or replacement

 

A couple of long runs seems to have done the trick. I hadn't realised SWAMBO was taking it in for a service this week and she asked them to test the battery - all OK.

We'll keep an eye on it over the next few weeks as well just in case but I reckon a series of short trips with aircon at full tilt probably took the edge off and not enough to recharge it sufficiently.

 

Thanks all for your help and advice.

Always a good idea to test, charge and/or take it for a blast.  WInter will be the big tell as to whether its ready to be replaced or not.  You can eke out more from a battery, but whether you replace sooner or later, you'll still have to replace at some point.  Best I got from a battery is around 8-9 years (Bosch, I think).  Anyhow, you're ok for now and you know how to replace when the time comes.

I would still Fully recharge it in the way I put before to ensure it's fully recharged as the more often it gets partials charges the quicker the battery will suffer and expire.

 

3 hours ago, SteveTheElder said:

asked them to test the battery

Probably ensure at least a quote for an expensive battery change.

 

Batteries like central heating problems often show up longer term issues at the first really cold snap of winter and if not fail then fail soon after just when loads of other people experience the same thing so shortages and narrower lack of choice of plumber and batteries and the issues at less than convenient times.

 

You can help to prevent this by preventative full charging of the battery a bit before the cold snap (and getting the c/h sorted in the summer).  Many drivers may not know the car battery likes about 20c ambient but self discharges twice as much at 30c and twice as much at 40c as 30c and with the use of a/c is getting a lot of use this depletes so when the cold weather arrives and the battery has problems holding the charge there is less charge to hold and the battery as already be weaken so lower state of charge and health when again it's going to have to do a lot of work.

 

The less work the battery can do the more work the car's alternator has to do, if one is kept weak it will eventually wear the other.

 

It's very difficult to compare how long something like a car battery will las as there are many variables to take into consideration even if comparing two cars that are exactly the same make and model of car and batteries, same as you and your neighbours using different amount of gas, electric and water, some use more than others and some are more wasteful and less maintenance than others.

 

People (including us) pay an arm and a leg to have the engine oil (and hopefully filter) changed annually to help keep it going, or if you done it yourself (like I sometimes do) it's a dirty messy job often rolling about on the ground, whereas battery maintenance such as preventative full recharging is very easy, clean hands work that can be working whilst your asleep.

 

Or perhaps the Dealership or garage might say the battery is fine.  Let us know how it goes on.

 

- A/C compressor is driven by the engine, but the fan does use electrical power, more so, should you turn it up higher.

- It's normal on modern cars for there to be higher static battery drain - things like remote door locks need to have a receiver listening for a signal, and possibly some other electronics are running. Thus, cars left undriven for weeks, really do need charging (or driving!)

- Batteries that are usually used on cars with smart alternators (almost all cars now) and stop start-systems are often coded because the cars computer makes a guess about the age of the battery, and number of starts if has done, in order to allow fewer stop-start cycles as the battery ages, and may choose to turn the smart alternator on a bit more often. Putting in a new code with a new battery tells the system the battery is new, or has slightly different characteristics for optimized smart charging.

- Battery voltage is not a perfect guide for understanding its true condition - sure, if a battery under zero load presents 12.7V or more (+/- some), it's probably going to start the car. It is a well-known thing that even if the battery cranks the engine, the voltage presented to the electronics can drop to a level so that the electronics malfunction and the car may not start, and even weird faults show up, like the radio thinking it has been rejected by the ECU. This is common on Up!/Citigo models, being a budget car - the electronics don't use an Up/Down DC-DC converter to keep a minimum voltage applied to the supply to the electronics (with a DC-DC converter, even say 8V would be converted to the necessary 12V). Anyone with caravan/MH leisure batteries knows why Up-Down DC-DC is needed!

- Last point - don't disconnect the battery voltage sensor. It's a false saving on reducing battery wear with stop-start - you use far more costly fuel over time, than the value of the marginal "life elongation" of the battery. Besides, Up/Citogo engines are very easy starters, and a very low-load on the battery by design...

 

 

On 16/08/2024 at 11:56, nta16 said:

Any recharging is better than none but quick (higher amps) partial recharging isn't best.

 

Its precisely what the vehicles alternator does every time after the vehicle has been started and with a minimum of a 90 ampere alternator, many far more than that, the charging rate will be 10 or 20 times what most battery chargers are capable of.

On 21/08/2024 at 13:15, nta16 said:

preventative full recharging is very easy, clean hands work that can be working whilst your asleep.

 

There is probably one journey in a thousand on a modern vehicle that results in the battery being less charged at the end than when the vehicle was started, a good example of that would be anyone with a stop/start vehicle daft enough to follow your repeated imploring and start a journey after a "preventative full recharging" where the alternator would not charge the vehicle until it had dropped beneath the 80% S.O.C. or whatever the B.M.M. software dictates.