2013 V70 D4. Low battery warning signal. Is it complicated.
 

I am getting Low Main Battery warning signal.

I read somewhere that changing battery on 2013 V70 can be complicated and expensive and will require a Volvo specialist.

I also read that the warning can be ignored for some months.

Something about accessing the brain and reprogramming for the new battery, and it can't be any old battery

It is five cylinder 2.0 litre D4 with 258,000 miles with SmartStop, so there is an auxiliary smaller battery in the system (Start/Stop works intermittently)

Any advice much appreciated

The car has two batteries. The smaller auxiliary battery I believe runs the car when the start stop kicks in or when you turn the car off and the radio stays on for example. When this is low it usually shuts the system down very quickly after the engine has stopped.

The main battery is very easy to replace and something you can do yourself. I have always had Volvo batteries because they have always been very competitively priced from the dealer compared to the likes of motor factors etc. plus you know it’s of quality but obviously you can choose from a wide range from various suppliers online.

The auxilary battery lives next to the main one. Also easy to replace. I have seen these advertised from Volvo for about £100.

The car does have a battery management system. Cars with smart charging alternators that use the CEM to control the alternator output use the battery aging data however I wouldn’t stop this from fitting a new battery yourself. You could always ask your local garage or Volvo specialist to reset it for you however think if you left it, it will sort it self out tho I have had to reset this on an XC60 after a battery change to stop the low battery warning coming up however.

It could be worth getting a health check done on both batteries so you can see which is good or bad. The auxiliary batteries seem to last a long time as both are still original on our S80 and XC70. My S80 had a replacement main battery when I bought the car at 8yr old as it failed the Volvo selekt health check but it had only done 30k miles so probably sat around for a bit.

There are videos on YouTube as to how to reset the battery monitoring system - that’s worth a try and costs nothing. Halfords and kwik fit do free battery tests I think, Tayna batteries are good value for replacements.

As said above the main battery is simple to replace as a diy job and not expensive, I would expect £100 or less.

The Volvan had its main battery changed under warranty due to the warning light, and it having been sat around during Covid. Intermittently the warning came back, getting more frequent, and Volvo diagnosed the helper battery was dying, so main battery was constantly trying to top it up. So 2 new ish batteries, but just had Covid again, and been laid up for nearly 3 weeks, and sure enough warning back on. A trip of around 30 miles, and all well again with S/S available agin. I do top it up with a charger now and again, if not used very much. It’s just one of those things.

Main Battery is easy to change. If you don't reset the BMS after installing a new battery, you will have irritating low battery messages or fake problems. There is no need not to reset it, because you can do it like this...

I got a 2013 V70 D3 five cyl, and this worked:

### Volvo cars 2010+ ###

Resseting Battery Monitoring Sensor when installing new main 12 V battery (without VIDA)
------------------------------------------------------------------------------------------
1) Ignition ON (press START for 5 sec) (key position II with engine OFF)

2) Dipped front lights ON

3) Rear foglights press 6x

4) Alarm lights press 3x (stays ON - turn OFF later)
------------------------------------------------------------------------------------------

Aux battery is not so easy to change, because it lives under Windscreen/Wipers Cowl Panel and one has to remove one or both wipers to get access to it. But, it rarely needs replacing and it doesn't require BMS reset.

Both batteries are required to be AGM type!

You can see the AUX battery here.

After you do the BMS reset procedure above, the battery symbol in the speedometer should flash 3x quickly. This way you know something has happened after all the button presses.

Not mentioned so far are that there are different battery types, your main battery will either be an AGM battery or Enhanced flooded type of battery.

Battery charging system
 

Graham Brown is correct the battery monitoring and charging circuit is extremely complicated. Unlike a normal alternator which has its own built in regulator the alternator has a separate set of diodes which feed a DC to the CEM for charging and as VOLVO say "conditioning" the battery. Trouble is it does not always work until it is too late. See forums on MY DASHBOARD LIT UP LIKE A CHRISTMAS TREE, LOSS OF DRIVE, ABS FAULT LIGHT,POWER STEERING COMES ON, etc..
This happened to me the Christmas tree one, just as the drive was lost.
When the car stopped nothing worked then on came the battery low warning after 30 seconds later, a fat lot of good is was then after the alternator had failed probably about 1 hour before the battery gave out on the journey and all the drive relays etc dropped out due to low voltage.

I've a 2013 V70 D4 5cyl Geartronic, owned from new. I replaced the main battery in Sept '19 with a genuine Volvo one owing to "battery low" messages. Never had any trouble starting. It's an easy replacement, detailed in the owner's manual. They're a bit heavy to lift in and out though.

Now I'm getting the messages again. Still starts instantly. I do periodically trickle charge it (in the manner specified in the manual).

A colleague has some reassuringly-expensive diagnostic kit (not Vida) and there are no charging/battery messages logged (there were a couple relating to a failed map update, a bulb failure and a transient sensor warning from ages ago), which he cleared.

I'm a bit unsure whether to keep going, or replace the main battery again, after only 4 1/2 years. The alternator's original. I'll be driving/ferrying from East Anglia to Shetland in a few weeks, and breaking down/dead battery would be really bad.

I’d be checking the auxiliary battery, your main battery should be still good but a test on both would be where I would probs start.