Colinporter

Hi all i have a trickle charger running on the rear consumer battery because that runs down with lack of use. Does the starter battery require a trickle charge as well or will that be ok as it's not running anything?

Thanks

thias

Should be OK.

Colinporter

👍👍 thanks.

mep999

I have trickle charger on consumer battery and nothing on starter battery. With covid lockdown I've not driven any distance since January, went to start my SL a few days ago and had a whole host of electrical failures all pointing to passenger can failure.
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Starter battery was reading 12.4v and after putting on charger for a few hours all electrical problems disappeared so will now be looking to trickle charger my starter battery as well until I can do more mileage.

Cheers

Colinporter

Thanks for that info. I'll check into mine for starting. Although it was started about 4 weeks ago.

danaw007

Starter battery does not need a tender, it will “tell” you when it needs replaced though. Just a tender on the rear. If you think you need a tender on the front it’s time to get a new starter battery.

Colinporter

My front battery is good it starts good every time.👍👍

thias

The symptoms you are describing, are pointing to a discharged comfort battery. This is the one in the back, many people don't know that. The small front battery is the starter battery. It should not need charging (unless you park the car for more than a few months) because it is usually disconnected from the cars electrical system until you turn on the motor. As long as the rear battery is charged, that is. If your front battery gets too low on charge, you will see a red battery warning in the dash. If you r rear battery is low, you will get the message, that your consumer devices are switched off. If your rear battery runs dry, you will get "all the error messages" - Chuck Norris style.

So, as I stated in my first post: Not charging the front battery should be fine.

matk

Hi, just to add my experiences I have a weak convenience systems battery, mainly due to my own arrogance through Winter, thinking I could protect it by just starting the car and running up to temperature every week. Each time I started the car all convenience features were disabled but would eventually restore. However I started getting a load of fault codes related to all sorts of stuff, lighting issues, Canbus down, idle speed increased due to low voltage, SBC alerts etc.

Finally did the right thing and put the rear battery on a trickle charger. The battery has recovered to the point that I can now start the car successfully with all convenience systems successfully on line.

When I then interrogated the car at that point I had a total of 63 stored fault codes relating to all sorts of stuff. I cleared them all down, test drove the car and since then not one of them (touch wood) has re-occurred.

Ive learnt my lesson! Trickle charger at all times for me now.

danaw007

It’s actually hard on a vehicle to start it weekly in the winter rather than to put it to bed. The heat attracts condensation as it cools down and invites the corrosion process. It’s best to either drive it once a week (if your in a decent climate) or mothball it surrounded by sticky traps and on a battery tender. Front battery just needs to be fully charged (usually is if you drove it in). I personally over condition the leather as well and use some Aerospace 303 on the rubber seals of the doors, top seals and even the engine weather seals. I use an interior cover and leave the windows down halfway. In the spring I uncover, wipe down the seats, check the tire pressure and it’s good to go.