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2007 Mercedes s 500 wagon electrical problems..?
when i turn on the head lights the passengers head light flashes about ten times and then stays off. i replaced the bulb but it is still the same
the driver side head light stays on perfect
2 Answers
- 5 years ago
Try stress testing your alternator.
Just turn everything electrical on, radio, full beams, electric windows, rear demister, blower fan, open all doors, everything you can basically. Do this with the car running.
If your engine stalls or you hear missfire or coughing then your alternator is going bad.
I'd suggest you get a multimeter, they are super useful and cheap. Test your battery, with the car off just check the terminals, see if it is outputting around 12-13V (more than 13V means your battery is dead). Then run the car and hook the positive of the alternator to your multimeter and ground it, it should be making around 13.8-14.2V ideally slightly (0.1V) more or less is fine. Then start to stress the electrical system as above, the voltage will drop on the alternator a bit, if it falls below 12-11V when the engine is idling your alternator is toast. Try opening the throttle, just rev it a bit 1500-2000 rpm the voltage sould jump back to around 14V.
Hope this helps, you can find videos on youtube on how to check your battery and alternator.
Good luck.
