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Electrical opinions needed..........

1K views 14 replies 7 participants last post by  Sincity 
#1 ·
Yesterday my battery died. Called roadside and they gave me a jump and said to get the system checked. Took it to the dealer and had them check it. They said everything checked out but that I should get a new battery. They wanted $200 installed and I decided to go elsewhere. I got one at Goodyear for half that price and it looked indentical. This AM as I was running my errands the battery light came on twice for just a few seconds and then went out. It has not come on again. When I got home I checked all the connections and everything was nice and snug. Any ideas? maybe a short?
 
#2 ·
Did the battery indicator "blink" or did it remain "lit"?

Either way, if the red charge indicator lamp lights up when the engine is running this means that for a moment or so while it is lit -- the battery is no longer charging, possible causes are: alternator malfunction or a broken poly-V-belt.
 
#4 ·
battery cost $109 plus tax

I replaced it myself on 2 ML's. both died exactly on anniversay month of 5 years old.

my lights would light up near end of battery light when battery couldn't hold full charge. ABS, Brake etc. Went away after new battery.

Your replacement battery might be too low on juice also for any of the reasons listed above.
 
#5 ·
VERY IMPORTANT Info:

Dunno about 99 model year ML's but on my 2003 owners manual it specifically recommends doing the following after any interruption of battery power (such as you mentioned):

 
#6 ·
Just came on for a few seconds.....

both times. It did not blink.
 
#7 ·
Thanks for the info S4 I will check on mine.
 
#8 ·
Of course I got the right specs.........

plus the battery I bought looks indentical. This one has a 850 cca and 1000 ca. The brand is Exide and the group number is 49.
 
#10 ·
Well it has.....

the same top as the OEM. The caps have the 2 slits in them so I guess you can remove and check the level. Do not know about the vents. This thing is huge though. 15" long and weights in at about 50lbs.
 
#11 ·
These problems happen all the time in my shop

Sounds like there is an intermittent problem with your alternator. The output may be failing at certain times. Unfortunately, it was probably at its best behaviour during the dealer's inspections.

Have them re check the charging system output, check for amperage and voltage drops from the alternator to the battery. Your problem may be along these lines.

Good Luck!
 
#12 ·
True --- I wonder why this was omitted from the list of things to check after power failure?
 
#13 ·
Thanks to all for the useful info.......

since this post all seems to be well. I guess the new battery just needed to charge for awhile. The only item I needed to reset was the radio code. The ML was without power for only a few moments. I will still have the electrical checked again tomorrow.
 
#14 ·
Battery

I had mine replaced last week after failing once, and two nights of slow charge. I paid $140.00 at the dealer w/installation and warranty. I was looking for an Optima battery (the best for off-roaders), but could not find one that met specs, so I went with the original.
 
#15 ·
BETO: You should have used Roadside Service. Free battery!

I also live in Vegas and called Road Side service (I ws stuck at a Home Depot). They changed a new battery for free. Vegas is notorious for killing batteries.
 
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