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AC_ML · 07-26-2004, 10:32 AM

First if your battery is already 4 years old, you should plan to change it anyway.

Get a cheap battery voltimeter that can go into your cigarrete lighter, and check first the battery voltage with the engine off. The voltage should read around 11.5-12.0 for a healthy battery.

Next turn on your engine, and the voltage should read around 13.5-14,0 volts. If it is below 13.0 volts, your alternator is not producing enough voltage to really charge your battery.

Check the contacts in your battery, if they are loose or if you find a dark oxidation layer, then your battery will not charge as it should and will not provide all the power it needs during cranking.

Most of the time, you can feel how your battery status is by the way your ML starts. If you feel a really snappy and healthy start (starter rotates nicely), then your battery is fully charged. If your ML starts kind of slow and weak, then you need to slow charge your battery since a drained battery will shorten its life span.

If I remember correctly, the the ML battery family size is #49. Excide and many others carry good replacements that last longer than the OEM's and are a lot cheaper.

If you do it yourself, make sure you have your radio code handy..

AC

07-26-2004, 10:32 AM	#6 (permalink)
AC_ML BenzWorld Elite Date registered: Aug 2002 Vehicle: Black 2005 ML 500 Location: Houston, TX Posts: 1,246	Get a cheap battery voltimeter that can go in your cigarrete lighter, and check first the First if your battery is already 4 years old, you should plan to change it anyway. Get a cheap battery voltimeter that can go into your cigarrete lighter, and check first the battery voltage with the engine off. The voltage should read around 11.5-12.0 for a healthy battery. Next turn on your engine, and the voltage should read around 13.5-14,0 volts. If it is below 13.0 volts, your alternator is not producing enough voltage to really charge your battery. Check the contacts in your battery, if they are loose or if you find a dark oxidation layer, then your battery will not charge as it should and will not provide all the power it needs during cranking. Most of the time, you can feel how your battery status is by the way your ML starts. If you feel a really snappy and healthy start (starter rotates nicely), then your battery is fully charged. If your ML starts kind of slow and weak, then you need to slow charge your battery since a drained battery will shorten its life span. If I remember correctly, the the ML battery family size is #49. Excide and many others carry good replacements that last longer than the OEM's and are a lot cheaper. If you do it yourself, make sure you have your radio code handy.. AC __________________ 2005 ML 500 Black, 18" AMG Wheels, 285/60R18 Falken Ziex ST/Z + Bi-Xenons(+ Drew's e-code mod), Yakima roof bars. Former vehicle 2001 ML 320 with 108K miles, when traded, and a large repair/defect history. After 3 years of owning my current 2005 ML 500, it has become another unreiliable vehicle with a very large/expensive repair/defect history..