V70: Electrical Trickle charger

[griston64]

Originally Posted by Tatsfield

Have a look at this thread which goes into a great deal of detail about battery chargers:

https://www.volvoforums.org.uk/showthread.php?t=260795

I quote page 333 of the Owners Manual for the 2012 XC70;

• The negative terminal on the battery
must never be used to connect a
jumper cable or a battery charger. Only
the ground point on the chassis may be
used.

Rewiring the negative connection for the CTEC permanent connection lead isn't a difficult job, even I could do it, and the manual is quite explicit about the matter. There is a picture here:

https://www.volvoforums.org.uk/attac...1&d=1481987329

I did state in OP that my manual said the same.Having said that a lot of jump lead instructions tell you not to connect to - terminal and everyone does.

I've connected it now so if anything is going to go badly wrong it's too alte now

[Tatsfield]

I don't think anything explosive would happen but you may find that over a period of time your car may not charge your battery as it should because you have bypassed the recharging monitoring system. It may be of no consequence at all but Volvo go out of their way to draw attention to the way chargers should be connected and the effects might be long term and allow your battery to be slowly damaged. Or, as you say, it may not!

[griston64]

Originally Posted by Tatsfield

I don't think anything explosive would happen but you may find that over a period of time your car may not charge your battery as it should because you have bypassed the recharging monitoring system. It may be of no consequence at all but Volvo go out of their way to draw attention to the way chargers should be connected and the effects might be long term and allow your battery to be slowly damaged. Or, as you say, it may not!

I'm hoping it's the latter

I will report back in due course

[jasons6930]

Bit of thread resurrection but entirely on topic!

I’m going connect a ctek 5.0s to top up the battery but what mode should I set the charger to?

In the v70 manual it states that a fast charger must never be used but I was going to put it on the ‘car’ mode rather than recondition mode so was concerned that wasn’t the correct setting!

[TimS]

I've got the same charger, and always leave it in the standard mode. My Diesel Geartronic V70 has an 'AGM' genuine Volvo battery, although I was advised in a thread here not to use AGM mode, which is more intended for higher capacity batteries. Certainly, leaving it to do its own thing has always been fine, especially when the car got almost no use during lockdown.

I attach the -ve lead to a small tang that protrudes in the centre of the engine bay, just under the windscreen, under the bonnet-sealing rubber strip.

[jasons6930]

Thanks

I used a small L bracket down at the front of the engine for the negative and positive to the battery.

So I’ve just switched it on and it automatically chose car mode and currently on light number 2 on the charger. For some reason the battery was at 12.2v which was probably why the low battery warning came up although I have been using the car for a few days so I would have thought it wouldn’t have dropped that low.

[john.wigley]

I would imagine that the risk of explosion while correctly using a modern 'smart' charger is minimal.

BUT ... I once left a battery connected to a non-smart trickle charger (3-4A) on the bench overnight. When I went into the garage the next morning there was a smell not unlike that of bad eggs. Yes, the battery had exploded during the night, blowing a substantial piece of the casing the length of the garage. The damage to the bench and the tool-box stored beneath it, caused by the escaping battery acid, was considerable and not an easy job to clean up. I was only thankful that no one was in the garage when it let go, as they would almost certainly have required an urgent trip to A and E.

Believe me, you do not want to run the slightest risk of the same thing happening to you, with possibly even more serious consequences. Please always follow the manufacturer's instructions when using tools and also take sensible safety precautions when doing so.

Regards, John.

[jasons6930]

Ok a quick update, now on number 7 green light so hopefully that should now be fully charged. I think when it hits number 8, that is the point it is on a maintenance charge and just monitors the battery for when the voltage drops and tops it up as required.

[george57l]

Originally Posted by jasons6930

Ok a quick update, now on number 7 green light so hopefully that should now be fully charged. I think when it hits number 8, that is the point it is on a maintenance charge and just monitors the battery for when the voltage drops and tops it up as required.

Ooh! My somewhat older CTEK unit only goes up to 7. You must have the Spinal Tap version! ;-)

[jasons6930]

Sorry it’s an MXS 5.0 not 5.0s!

CTEK MXS 5.0 Battery Charger with Automatic Temperature Compensation, Black https://amzn.eu/d/0JQITCX