W209 Red Battery Light
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Joined: Jul 2016
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12 E63, 12 ML350, 05 4RUNNER V8
W209 Red Battery Light
My 07 clk550 has the red battery light come on whenever i floor it then goes off after i restart the car and drive like a normal human being. The belts look ok, the battery is new, im thinking its either the alternator or there is a pulley issue because i heard a funny noise from the engine bay which sounds like a belt was slipping on a pulley. Any thoughts?
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Joined: Oct 2012
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From: Florida
2002 CLK 55 AMG cabriolet Eurocharged
I would start by removing the belt and rotating each moving part in the loop.
Resistance, or a glitch in pulley bearing rotation might be the culprit.
If it takes little effort to move the belt tensioner then it becomes a suspect.
An overcharging alternator might give the battery light as well.
Start with a new belt. It is a maintenance wear item regardless. Take note of oil or coolant contamination on the belt as well.
Cheers, Gator
Resistance, or a glitch in pulley bearing rotation might be the culprit.
If it takes little effort to move the belt tensioner then it becomes a suspect.
An overcharging alternator might give the battery light as well.
Start with a new belt. It is a maintenance wear item regardless. Take note of oil or coolant contamination on the belt as well.
Cheers, Gator
Thread Starter
Junior Member
Joined: Jul 2016
Posts: 23
Likes: 0
12 E63, 12 ML350, 05 4RUNNER V8
So I diagnosed it as an alternator due to the voltage being at 12 with the car running. I ordered a bosh alternator that i was gonna install tomorrow...but after doing some research i see people have probelms with the voltage regulator could this be the main issue? should i replace it as well while im in there?
thanks
thanks
MBWorld Fanatic!
Joined: Oct 2012
Posts: 1,427
Likes: 100
From: Florida
2002 CLK 55 AMG cabriolet Eurocharged
I am an avid regulator changer on many benz in the past.
But to do it with success requires some alternator rebuild knowledge.
Replacing the regulator with brushes is easy, two screws. Big problem is the commutator slip rings that the brushes ride on get heavily grooved. The new regulator will work but not efficient.
What I do is place the rotor from the alternator in an electric drill locked in a vice.
At Low RPM hold a flat file on the brush commutator slip rings until all grooves are gone. follow up with polishing emery. Two new bearings WaLa.
Fresh Alternator with two hours bench time for $50.00
Your new Alternator will come with Regulator
Cheers
But to do it with success requires some alternator rebuild knowledge.
Replacing the regulator with brushes is easy, two screws. Big problem is the commutator slip rings that the brushes ride on get heavily grooved. The new regulator will work but not efficient.
What I do is place the rotor from the alternator in an electric drill locked in a vice.
At Low RPM hold a flat file on the brush commutator slip rings until all grooves are gone. follow up with polishing emery. Two new bearings WaLa.
Fresh Alternator with two hours bench time for $50.00
Your new Alternator will come with Regulator
Cheers
Last edited by GatorMB; Jul 2, 2017 at 10:01 PM. Reason: added content
Super Member
Joined: Jun 2015
Posts: 503
Likes: 38
From: South Africa
2004 CLK55 AMG W209
What I do is place the rotor from the alternator in an electric drill locked in a vice.
At Low RPM hold a flat file on the brush commutator slip rings until all grooves are gone. follow up with polishing emery. Two new bearings WaLa.
Fresh Alternator with two hours bench time for $50.00
Cheers
At Low RPM hold a flat file on the brush commutator slip rings until all grooves are gone. follow up with polishing emery. Two new bearings WaLa.
Fresh Alternator with two hours bench time for $50.00
Cheers
