michakaveli

I have a new Interstate battery installed, 3-4 weeks old,[important note I had to add]. I noticed within the past month I've been driving my '97 E300 I've had about 3 times, including today, when she has seemed a little difficult to start,like a weaker battey so to speak. Earlier today I pulled my car into the garage at work, shut her off but left the headlamps on to warm up the lenses [for something else I was doing]. Left them on for about 10 minutes then shut them off. Mind you there were no other accesories on with the motor off, except the headlamps, no radio. After 45 minutes it was time for my to head for home. I hopped in and the car wouldn't start, wouldn't even tick. I hooked up one of those wheeled battery chargers. To no avail, but she did click a few times. When she was connected to the charger, I went through the normal sequence of events to start it. By the time the glow plug light went out the lights on the dash were really weak. I then tried connecting the charger directly to the battery under the seat, still same s***. gave her a minute or two then tried again. I believe I tried 2 more times. I don't know if this helped, but on my final try I put the pedal to the floor and started cranking it. Suprisingly it never clicked just started cranking very weakly but cranking, after a while she turned over. Hurray! I backed her out and I saw a message on the console stating ABS malfunction or something, but it went away on it's own after a few seconds. But never did I see a battery charge alert. Odd? On the 2-3 mile travel home I was only running the parking lights and fog lights, no heat, defroster or radio [just to be on the safe side]. I got home. Shut her off for a minute then tried started her back up and she started with no problem... Whats going on? I connected a trickle charger at home too and she was charing at 9amps RMS. DEfinately seemed like a dead battery. When she was running, we turned on the lights, defroster and rear defroster and reved her up alittle a couple of times and a slight increase in headlamp power was seen. Aren't the voltage regulators in these late model benz less tolerable to such voltage differences? I'm gonna take her to my mechanic tomorrow to test the battery and alternator. Any ideas guygs. She's got 124k on the clock, and am assuming the alternator is still original, no records of replacement.

BIG RON

I don't think you have a major problem. Check your belts , battery connections, and your battery. There are some bad batteries. I do hope it is a miner problem. Big Ron

michakaveli

I checked the battery connections and the ground under the seat.. Those look solid.

E320

How old is the original battery?You might need to replace it soon and check if your alternator is charging the battery,Use a multimeter to check the voltage.

michakaveli

Went to my mechanic today and had the battery and alternator checked. I've been running my multimeter to keep an eye on my voltage. This seems like a "ghost " problem, and only surfaces when it wants to.

The battery is new, 3-4 weeks old.

phungpho

Michakaveli,

You're almost right but you still forget another major problem: 'Shortage'.

Basically, if you can not start the engine then your battery is dead. There are 3 reasons:
1. The battery is 'really' dead. In this case buy a new one. When you replace the old one, make sure the new one has at least the same 'cramps' as the original one.

2. If the battery is new, but has no juice. The first cause is the altenator. If the altenator is dead then replace it. In this case, there's a warning message depends on the car and the model. It could be a 'battery' or an 'Altenator' warning.

3. The battery is new, sometime there's juice and sometime not (like your case). So, the problem here is either the altenator is not completely dead or there's a 'Shortage' somewhere. In this situation, it's not easy to ping point the problem. You need a good electrical guy. Those regular mechanical guys most of the time can not fugure out the problem. It happened to me before and finally I had to trade it in for a new car. It was a VW GTI with an electrical problem.

Good luck.

michakaveli

Phungpho, I definately agree with your #3. I think the only thing I can do now is install a digital voltage meter to be able to monitor the voltage. Hopefully It'll last till it gets warm again. Anyone ever change the alternator on one of these? IS it possibe that runnign the headlights including the highbeams for 10 can kill a battery soo large? I know that a diesel uses an extrardinary amount of cold cranking amps. I used to run my car stereo system with two high power amps while I would detail my car in the summer for at least an hour at a time on my plymouth acclaim V6 with never a problem of it starting after.