PeachParts Mercedes-Benz Forum - View Single Post

JimSmith · #2 05-23-2002, 04:58 PM

Village Idiot,

I can't answer your question on the window working with the power off, as I have a Euro model with hand crank windows.

My 1986 190E 2.3-16 has the little Voltmeter in the three guage cluster in the console too. The needle flicker you see when you step on the brake or turn the lights on, or turn the blinkers or 4 way flashers and so on, is pretty normal in my view. The Voltage regulator needs a fraction of a second to respond to the demand for power, and in that instant the Voltage droops slightly. While driving, it is normal for the Voltage to be a little lower the more things you turn on, but not go below the 13.4 or so Volts you should have with nothing running at idle. The droop and needle flicker may be more pronounced at idle, as the alternator and regulator have no other parameter to work with to really balance the load. At higher rpm the alternator can make more juice and the regulator can keep things balanced at a more favorable Voltage. I see these effects all the time and my car has 206,000 miles. The head was recently removed, refurbished and put back on but we have a few items left before it will be running. Expect that this weekend. So, I can not recall exactly how much the Voltage droops or what the readings normally are at the moment, and also can not go out and turn it on to check.

I have used three batteries in the 16 years I have owned the car. I replaced the original one (Varta) at about 7 years, with the next (Sears Die Hard) lasting just over 5 and the one in there about (another Sears Die Hard) two years old now. I did have a defective Sears Die Hard last only a few months, but it was replaced free. So far, no issues with the alternator. Good Luck, Jim