SL/R230: Red BAttery light - can it be caused by high voltage?
Thread Starter
Member
Joined: Aug 2018
Posts: 147
Likes: 21
From: SF Bay Area
SL55 AMG, Audi S6 V8TT, Audi Q7 3.0 SC
Thread Starter
Member
Joined: Aug 2018
Posts: 147
Likes: 21
From: SF Bay Area
SL55 AMG, Audi S6 V8TT, Audi Q7 3.0 SC
The update is that if i keep the rear battery plugged to the CTEK trickle charger when the car sits parked for few days, the red battery light does NOT come on.
I've had the red light come on only once in the last few weeks and that was after repetitive engine on-off situation (short trips) and sitting on a parking lot with the engine off and the stereo running for 10 minutes.
My AGM battery is not covered by any warranty at this point, so eventually i will have to buy a new one.
I tested it with two different battery testers and they both showed "good battery" or "good battery - recharge".
Even when fully charged it always measures actual CCAs under the value listed on the label. Battery is rated at 760 CCA and it measures around 600-630 CCA.
The front battery, under the hood, (mercedes branded) tested "good battery" multiple times, even if the car sits for weeks.
I've had the red light come on only once in the last few weeks and that was after repetitive engine on-off situation (short trips) and sitting on a parking lot with the engine off and the stereo running for 10 minutes.
My AGM battery is not covered by any warranty at this point, so eventually i will have to buy a new one.
I tested it with two different battery testers and they both showed "good battery" or "good battery - recharge".
Even when fully charged it always measures actual CCAs under the value listed on the label. Battery is rated at 760 CCA and it measures around 600-630 CCA.
The front battery, under the hood, (mercedes branded) tested "good battery" multiple times, even if the car sits for weeks.
