SL/R230: SL 500 2005
10-26-2022, 05:19 PM
#26
Super Member
Get that current soak test done on that battery.
As mentioned, measuring static voltage is only one factor in battery performance, and measuring the voltage with the car running tells you nothing about the condition of the battery, just the charging system.
I'd be pulling the SAMs though and looking for any water damage to those modules.
As mentioned, measuring static voltage is only one factor in battery performance, and measuring the voltage with the car running tells you nothing about the condition of the battery, just the charging system.
I'd be pulling the SAMs though and looking for any water damage to those modules.
11-12-2022, 11:26 AM
#27
Junior Member
Thread Starter
Get that current soak test done on that battery.
As mentioned, measuring static voltage is only one factor in battery performance, and measuring the voltage with the car running tells you nothing about the condition of the battery, just the charging system.
I'd be pulling the SAMs though and looking for any water damage to those modules.
As mentioned, measuring static voltage is only one factor in battery performance, and measuring the voltage with the car running tells you nothing about the condition of the battery, just the charging system.
I'd be pulling the SAMs though and looking for any water damage to those modules.
Finally managed to get it booked in .
Charging was fine to begin with ,then the rear battery jumped to over 18volts .
The front was fine ,then dropped below 12volts .
Fingers pointing towards the alternator .
11-12-2022, 05:42 PM
#28
Super Member
Highly likely it's the regulator, not the alternator. If so then this is available separately.
Over-voltage to the battery module (which charges the front battery) probably caused it to shut down and stop charging.
Over-voltage to the battery module (which charges the front battery) probably caused it to shut down and stop charging.
11-12-2022, 05:48 PM
#29
Junior Member
Thread Starter
11-12-2022, 11:06 PM
#30
Super Member
It's attached to the alternator, yes. I haven't worked on mine but you can change it without removing the alternator I believe.
It was an early known trouble spot. Mine had the alternator replaced under warranty when the car was a year old.
It was an early known trouble spot. Mine had the alternator replaced under warranty when the car was a year old.
Last edited by Tom Manning; 11-12-2022 at 11:27 PM.
The following users liked this post:
WBW (11-14-2022)
11-13-2022, 02:05 AM
#31
Junior Member
Thread Starter
11-16-2022, 05:13 AM
#32
Junior Member
Thread Starter
