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Is this an alternator problem?

Hi, hope someone here can help. I can’t figure it out: When the temp is cold (under 40 degrees) & my car has not been running for a few hours, whenever I start it the Alternator / Battery light comes on. My SRS & ESP lights come on & the car engine idles very roughly. If I let it run for a minute or 2, then everything goes back to normal. I replaced the battery just 2 months ago (the previous one was only 1 year old & has SAME issues).

Not sure what is going on but if anyone can give insight I’d very much appreciate it.


Make ?
Model ?
Model-Year ?
How Many Miles On This Cold-Blooded Mobile ?


Sorry, it’s a 2003 MB C230 with 144k miles!

Clean the ground connection from the battery at the motor would be step 1.

Thanks Barkydog, I’ll give that a try. As you can tell, I have almost no experience here.

Many fault codes and warning lights set for low voltage conditions. A competent shop should thoroughly test your charging system. If the idle voltage is too low, a voltage regulator will often fix your problem. I worked at a Benz dealer for many years, and charging problems were often resolved with a new regulator.

I forgot to mention the "reason"
When it’s cold the brushes sometimes stick. After operating for some time, the brushes and everything else in the alternator warm up and start behaving.

Is the belt tight? A belt gets ‘sticky’ when it heats up and if not quite tight enough it might slip until it gets warmed up.