C70: Battery charging

[upv5]

If you only do low mileage especially at this time of year with lights on, heated screens, heated seats etc your battery will get low.
I suggest buying a simple charger from a reputable maker and give it a full charge which may take 24 hours or more. Good ones have polarity protection and an indicator when fully charged. Leave the bonnet ajar for ventilation.
You can safely do this with the battery attached and you are correct it is safer to connect the negative to an earth on the other side of the engine bay, I use the engine lifting eye. Disconnect this first when you remove the charger so if there is a spark it is not next to the battery.
You will probably find you only have to do this once a year as during the summer the electrical loads are much lower.
Batteries do have a limited life but Volvo original and Bosch silver often exceed 10 years if looked after.

John

[phil1968]

I do wonder if you have an underlying problem because I could leave my D5 C70 for up to a month & it always started no problem. And diesels are harder on their batteries than their petrol counterparts

[Bob Meadows]

https://www.ebay.co.uk/itm/Vehicle-C...gAAOSwFp5crVCh
These voltage testers are quite handy to have- a quick & cheerful - economical fitting to have in the car: ~ Bob

[canis]

Originally Posted by capt jack

I happened to have use of a newish Fiesta a few weeks back, and it would stop the engine at traffic lights etc, and then restart when you pushed the clutch down. However, all the lights, heaters, audio continued to work even with engine off.

Agreed. Y'know, it really gets on my nerves. In a low battery situation, what I rally want to do is just give all power to the starter motor. But as sooon as you even open the door and reach in to kill the courtesy light, dashboard panel lights which can't be switched off. Can't even ensure the blowers are switched off because it's all electronic and the interface isn't showing yet. Turn the key, sat-nav's, telly screens, etc. All try to switch on sapping the battery of it's last few volts, and in this condition I'm trying to start an engine drawing, what, 80amps at a guess?

I'm pig-sick of "intelligent" cars. I just want everything on a toggle switch, in a bank of switches in the middle of the dashboard. I could tell at a glance which circuits are switch off, if they're all up everything is off. Simple. Honestly, all these features such as automatic rear wipe - why do I want that? What was wrong with a switch and me switching it? Why can't I be the decision-maker and the car just do as it's told. I wish it would stop trying to be clever!

[SwissXC90]

Originally Posted by Ian21401

We could live with the unnecessary warning but the shut off is totally unacceptable.
However, what can be done about it?
Is it possible to update/amend the software?
Dealer is saying not possible.

Yes you can change the software if you are the original software development company, and can push it through all the test and validation and release channels.

Realistically, that's not going to happen.

I also drive infrequently and have one of these to monitor my XC90 battery:
https://www.ctek.com/products/vehicle/ctx-battery-sense

And one of these to charge it up overnight once a month or so:
https://www.ctek.com/products/vehicle/mxs-5-0

That way I keep my battery in top condition and I know when I should charge it or not.

[Ian21401]

Originally Posted by Bob Meadows

https://www.ebay.co.uk/itm/Vehicle-C...gAAOSwFp5crVCh
These voltage testers are quite handy to have- a quick & cheerful - economical fitting to have in the car: ~ Bob

Pure coincidence. Have just bought one of those devices which also has twin USB outputs should I need them. Have had it in my 940 for a few days now. Just bought and fitted it out of interest.
Curiously, after standing outside overnight, at first switch on shows only 11.0 volts. Starter operates correctly and engine signs over and starts no problem. When engine running device display varies up and down between 13.2v and 13.4v. Haven’t yet checked to compare it with my battery terminal voltage. I checked my battery terminal voltage with a multimeter a few weeks ago after reading that thread about uprating an alternator. (Yes Dave, I checked and replaced the multimeter batteries but the results were no different.)
Before starting engine: 12.7 v
No electrical load : at idle = 13.73 v
at 1500rpm = 13.73 v
Everything switched on: at idle = 12.4 v but gradually reducing.
at 1500 rpm = 12.9 v
After testing battery = 12.38 v
Charged overnight with very basic charger, started at 1.9 amp.
Following morning charger showing 1.0 amp.
When disconnected battery voltage = 12.38 v same as before charging.
Car has never refused to turn over normally and has started easily as usual.

[StanC]

My 1996 960 gets a 50 mile run once a fortnight. The rest of the time it sits in the garage connected to a CTEK smart charger. The present battery, a Bosch, is 15 years old and (touch wood) is still working like new.

Some test work I did a few years ago, which led to me buying the smart charger, showed that when the car is parked-up in the garage with everything, including the alarm, switched off the drain on the battery is about 40 mA. This drain is mainly down to the ECU, the clock, the radio code and the electric seat memory function. The drain of 40 mA might not sound much, but it equates to 1 Ah per 24 hours that the car is parked, or 7 Ah per week. On a 77 Ah battery that's not much but when the car is parked for a fortnight at a time even a long-ish run might not put back 14 Ah of charge and the battery slowly discharges over a period of months. And when a battery sits in a partially discharged state for weeks on end it loses its ability to accept charge, which results in a vicious circle, with the battery charge spiralling downwards. With the battery permanently connected to a smart charger this doesn't happen and the battery is maintained almost like new.

Stan.

[green van man]

Mmm. My xc70 sits on the drive for months, gets a run of 186 miles then sits for another couple of months. Not failed to start yet and not had low volts warning. Battery probably original and 10 years old but defiantly 6 because I've not put a new battery on it.

Only time I've had a problem is when I've left the lights on , mine can be switched off on the switch but that means if you leave side lights on its a flat battery, then overnight charge and all is good again.

Never had a problem with batteries on my volvos, 460, S40 V70 or XC70. Yes they eventually wore out and needed replacing but ongoing problems no. Prehaps my likeing of poverty spec cars has something to do with it. All the toys are just more things to go wrong.

Paul.

[Clan]

Originally Posted by capt jack

In 42 years of car ownership - at that includes more than a dozen Volvos - I've never had to give a car battery regular top up charges. Of course I've bought new batteries - I had to get one last week for my 97 S90 as it happens - but I've always regarded the battery as "service consumable" - a bit like tyres, brakes and exhausts. Something that will last a good while, but not for the life of the car.

I do wonder about cars with automatic stop-start systems though. I happened to have use of a newish Fiesta a few weeks back, and it would stop the engine at traffic lights etc, and then restart when you pushed the clutch down. However, all the lights, heaters, audio continued to work even with engine off. I guess that engineers cleverer than me have thought it all through, but I could quite believe that a car with this technology used predominantly in slow traffic would tend to go through batteries rather more quickly than cars without.

Jack

The main battery is an AGM battery , well up to te task , and when you are stopped with all the electrics draining , the power comes from a small secondary battery :-)

[Clan]

Originally Posted by capt jack

In 42 years of car ownership - at that includes more than a dozen Volvos - I've never had to give a car battery regular top up charges. Of course I've bought new batteries - I had to get one last week for my 97 S90 as it happens - but I've always regarded the battery as "service consumable" - a bit like tyres, brakes and exhausts. Something that will last a good while, but not for the life of the car.

I do wonder about cars with automatic stop-start systems though. I happened to have use of a newish Fiesta a few weeks back, and it would stop the engine at traffic lights etc, and then restart when you pushed the clutch down. However, all the lights, heaters, audio continued to work even with engine off. I guess that engineers cleverer than me have thought it all through, but I could quite believe that a car with this technology used predominantly in slow traffic would tend to go through batteries rather more quickly than cars without.

Jack

If volvos are stored for any reason volvo recommend a top up charge every 3 months , you should not need a charger on there every week ...