1999 E300 Battery Charge Message
 

I have a 1999 E300. I just drove it 1200 miles in 4 days. After 450 miles I stopped to get diesel started it up and the Battery Charge Message appeared. I parked it for 10 minutes and restarted it. The message was still there. Started to drive it, put on the brakes and the message disappeared but left the error icon on the readout. I drove it another 100 miles home. The next day there was no error message or any indication anything was wrong. This is the second time this has happened. The first was 8 months ago when I bought it. On the 3rd day of the 2200 mile journey home it appeared when I started it. Drove it 600 miles that day. Same experience no indication anything was wrong the next day. Never had another Battery Charge Warning until last week. It seems to be related to long trips. Is this an indication that the alternator is starting to go bad? Or is this related to some faulty electrical? Anyone ever experienced this before?

Thanks for your help!

Mine exhibited this exact periodic problem until I found a small coolant leak from the thermostat housing was dripping onto the pulley at the alternator. I replaced the housing/gasket/belt and never had a problem since then.

Was this leak visible under normal driving conditions or only after long trips?
Thanks
Tyler

How old is your battery? If more than a couple of years old have the charging system load tested. Battery, voltage regulator and alternator are all independently replaceable.

Actually I only saw the dried evidence of the leak. I think mine would leak after shutting down and sitting overnight. You can examine the bottom of the housing and see easily if there is evidence of any past seepage.

Also, you might just need a new belt and tensioner spring. If you don't see evidence of any leaks I would try that first. The belt can't slip at all afterstartup or you will get that message.

I also have heard people having trouble with the alternator pulley itself.

If its the original battery, or even 5 years old, change it. I had the same problem, usually in cold weather. New battery = no more problem.

Yep...same problem. Mechanics have told me that with the battery being under the seat it takes a beating. Also there is some voltage drop over the length of the cable because of the distance away from the charging point which would be the alternator under the hood. The heat under the seat and the distance from the alternator shortens the life of the battery.....if that makes sense?
New Battery...No Problem

In my case the PO had the dealer check it which they "diagnosed" as a battery so they changed it but it apparently didn't fix it since it continued to occaisionally give the charge warning even after that and after I bought it.

It does not take much in the way of contamination on the belt to cause slippage and when these cars first start there is a large drain from the GPs which continue to work for a minute or so after startup so if the alternator is not putting out peak power it will trigger the warning.

In short, yeah, if your battery is old replace it but if it is not then make sure the connections at it are good, clean and tight and look at the belt and pulley next. Good luck.

The PO had the battery replaced April 2006. Luckily I got the previous service records. Looks like he was having the same problem also. Didn't see any signs of a coolant leak. How do I get the charging system load tested?
Thanks for all your help!!

I'd examine the belt and tensioner spring next then. If the belt is old replace it, its not too expensive and you can save the old one in the trunk for an emergency. Same with the spring, buy one and replace the one on the car and save the old one with the belt in case of failure.

Most garages and many parts houses can load test it for you while in the car.

A slipping belt will cause that message as was pointed out. If that is occuring you may find some glazing showing on the underside of the belt.