XC60 battery change

[Mikesmith181]

Afternoon all, I have a 2012 xc60 diesel and since the colder weather has started I’ve found my car is taking longer to crank over so I’m going to check my battery health and suspect it will need to be changed, I have noticed there is 2 batteries, the main one in front of the passenger seat under the wipers and a smaller one more in the middle. What is the smaller one for? Am I best changing both and if that one is good but the main one going bad will it effect the test results?
TIA

[NigelDay]

The smaller one will be the auxiliary for the stop-start system. It might be worth going to a main dealer to check which of the two is 'tired'. It's been discussed before, but main dealer batteries are not much more expensive than 'high street' and at least you will get the right one(s).

[Clan]

Originally Posted by Mikesmith181

Afternoon all, I have a 2012 xc60 diesel and since the colder weather has started I’ve found my car is taking longer to crank over so I’m going to check my battery health and suspect it will need to be changed, I have noticed there is 2 batteries, the main one in front of the passenger seat under the wipers and a smaller one more in the middle. What is the smaller one for? Am I best changing both and if that one is good but the main one going bad will it effect the test results?
TIA

As said above , good advice . The small battery is used to keep the electrics going whilst stopped , the main battery is always used for starting the engine .
Very unusual to have a battery fail this soon .. There is a built in battery test in the car which can be activated by the dealer garage , best get this done and see what state the battery is in , it may just need a charge . The small battery has never given problems yet as it is always fully charged .

[AndyJudge]

Just had said test done on mine & it showed up the battery was getting past it's best.

All replaced at the dealer with minimum of fuss. XC60 D5 Battery was about £112 inc VAT fitted.

[Whiterdesign]

Don’t forget that as the weather gets colder the glow plugs will be taking longer to heat up the cylinders, normally the engine will not start to crank until the glow plugs reach temperature.

[Mick787]

Excellent post Whiterdesign. I can’t imagine a dearship giving such advice, nor saying, ‘nothing wrong with the battery’.

[Mikesmith181]

Originally Posted by Clan

As said above , good advice . The small battery is used to keep the electrics going whilst stopped , the main battery is always used for starting the engine .
Very unusual to have a battery fail this soon .. There is a built in battery test in the car which can be activated by the dealer garage , best get this done and see what state the battery is in , it may just need a charge . The small battery has never given problems yet as it is always fully charged .

The built in battery test, is that activated with VIDA, as I have VIDA and dice, so could do the rest myself, would you happen to know how to do it?

[Clan]

Originally Posted by Mikesmith181

The built in battery test, is that activated with VIDA, as I have VIDA and dice, so could do the rest myself, would you happen to know how to do it?

you say the engine is taking longer to crank , what does this mean , is it slower turning over or is there a delay when you press the start button before the starter engages then it starts ok ?

Battery test is in one of the menus under communication CEM if you have it , do you have a little battery monotor with a wire on on the negative battery terminal ?

[Mikesmith181]

Originally Posted by Clan

you say the engine is taking longer to crank , what does this mean , is it slower turning over or is there a delay when you press the start button before the starter engages then it starts ok ?

Battery test is in one of the menus under communication CEM if you have it , do you have a little battery monotor with a wire on on the negative battery terminal ?

It just seems to crank slower and a little longer, could be nothing, I just wanted to be prepared really. I’ve not looked at the battery as yet, would I need that to perform the VIDA battery test?

[Clan]

Originally Posted by Mikesmith181

It just seems to crank slower and a little longer, could be nothing, I just wanted to be prepared really. I’ve not looked at the battery as yet, would I need that to perform the VIDA battery test?

yes it needs to have the battery monitor on the negative battery terminal clamp for that .