1984 Mercedes-Benz SL-Class - Battery light stays on

Battery light on dash stays on.

And??? Take it in to your mechanic to be diagnosed before your are stranded.


That light indicates a probable problem with the charging system and/or the battery itself.
How old is that battery?
Are there any other symptoms, such as fluctuating function of various electrical devices in the car?

Unless the OP wants to pay for a tow–in addition to battery and/or alternator replacement–he should take the car to his mechanic today.


Do you have the owner’s manual? If not, maybe you can get one on line from MB or find a printed one on line. It will tell you what an illuminated battery light means.

If that light turns on when the engine is running, it usually means the battery isn’t getting enough current from the alternator to keep it charged. If so the engine will soon stop running b/c a discharged battery will result in no-sparks to the spark plugs. A common cause for this is a loose accessory belt. Do you sometimes hear a squealing sound, especially when the engine is just warming up? Or there’s wet weather? If you’ve been living a good life, all that may be necessary is an alternator belt adjustment.

Obviously an alternator problem, either the belt or the alternator itself. and for a 36 year old car it could easily be either.

Take it to a competant mechanic to get, get a diagnosis (both repairs are relatively cheap) and get prepared for a transmission repair (expensive) which is typical for for these cars.

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I see this as being the alternator in the end

There’s a chance you might only need the voltage regulator assembly which includes the brushes for this application

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