Hey everybody. I am new to the forum. I have a 2005 C230 Komp. I have done a little searching but need some help. I just got the Battery/Alternator warning light. I have noticed lately that the power seems to be surging occasionally. Especially when stopped at a red light. It almost died yesterday at a redlight. I just went to Autozone and Advanced to have a test run. Here are some numbers: Battery- 12.31V, 457 CCA/ Alternator- 13.95 V 2.8A No load and 14.07V 3.8A Loaded. It says to replace battery. The car starts great so I was thinking it was probably the alternator. I have also just been reading about the issue with the leaking cam sensor/bad wiring harness issues. Looks like there is a little oil inside the can snesor connection. I'm kinda freaking out- somebody tell me it's jsut the battery! I jsut don't want to buy a battery if it is something else. Thanks for any help.

 

That alternator reading looks fine. The battery is in line with what my battery reads after sitting overnight. 12.7 is full charge and 11.7 is dead, IIRC. And the CCA is 950 when new on the OEM batteries, I think.

I'd say those alternator numbers look just fine. But the battery number looks fine, too, as my car starts fine and runs fine even with a 12.3V reading in the mornings.

How many miles you have?

 

around 56K...Any ideas? I have been reading that some people have had problems with their voltage regulators on the alternator. That would maybe explain my lights surging? It's my wifes car, so she has just told me something this week. She said that she was sitting at a red light last week and the interior lights would dim, rpms would surge back and forth, and the radio actually turned off. She said it didn't stall, but it sounds like it was close.

 

ok i would replace battery for the heck of it the cca is half of what it should be so it will need it soon anyway. if that doesn't fix it i would say voltage regulator too because of the dimming.