Clk 320 Convertible W208 Won't Start

[sattie_c]

I don't use my car everyday as I have the use of my wife's mercedes A class while she's on maternity. I wanted to use my car today so I went to start it and it clicked but didn't start. Just felt like a flat battery.

This evening I jump started and it was fine. Kept is running for at least 30 minutes. Seemed OK. I left it for an hour and it doesn't start again. I measured the voltage of my battery and it read 10.40v. In comparison to my wifes mercedes that's giving 12.33v.

Is it the battery that's on it's way out or my alternator not charging the battery.

I would appreciate any advise.

TIA

 

[Uncle Benz]

It could be either. Jump start it again, and put your meter on the battery with the engine running. You should see something in excess of 13 volts if the alternator is OK. It is not the most accurate way to check charging rates, but will suffice to eliminate the alternator from your enquiries. If the alternator checks out OK, give the battery an overnight charge with a decent battery charger just to make sure before buying a new one.

 

[sattie_c]

I've heard that the battery life is roughly 4 years. My CLK is 2001 so more likely to be the battery??

 

[television]

Sounds like the battery, thats a good age