2_point8_boy

1. I had my center console apart last night and I noticed that there was a dual wire connector that doesn't go to anything. On of the wires is grey and looks like it connects to my E-Brake switch. Is this the connector to the power hatch release?


2. Does the alternator "turn off" after it senses that the battery is fully charged back up? If I drive around, I notice that about 10 minutes aftter starting the car, the voltage guage showes right around 12 volts. 10-15 minutes later it shows 13-14 again. I know that the alternator is good because it's brand freakin' new. The cars' done this since I got it, and I just thought to ask about it. The Battery is new too.

2vmodular

make sure that the drive belt is not glazed and that the tensioner still has some strength left to it. also look for signs of corrosion on the high current positive lead from the alternator and the ground straps.

2_point8_boy

yeah, all the electrical was the first thing I checked. It's all fine. Doesn't affect drivability, and the battery stays charged, I was just wondering is all. Belt is new and tensioner is too.

2vmodular

perhaps there is a problem with the voltmeter guage or wiring to it. to check, pop the hood & connect a voltmeter directly to the battery

additionally, keep in mind that the alternator requires an excitation voltage to charge.

2_point8_boy

yeah I learned all about the excitation current to make the alternator work.

I helped a buddy of mine build a sand rail and the VW wiring diagrams showed nothing of an excitation wire, just the warning light that it's not working.

We went out to the dunes and went on a night ride. Half way thru, we were going up a dune and the engine died. Then we noticed that the lights were dim. Couldn't start it back up, so we sat out in the dunes drinking beer for an hour waiting for our buddies to get their truck to tow us home back to camp.
Once we got there, someone explained the excite wire, we wired it up real quick, jump started the motor and off we went.

Kind of a hard way to learn about engine electrical.

anyway, enough story sharing. I tested all of the wiring for continuity with test leads, everything seems to be ok there. My car's probably just on drugs or something... :sillylol:

1991tealRSt-topGuy

this is the worst assumption you can make

Danno

If the battery is staying up it's probably OK. Typically when you first start in the morning the guage after it start's running should read on the high side indicating a charging situation to replace capacity the batt lost during starting. The alt will charge this way until the battery terminal voltage comes up to a predetermined level set by the voltage regulator. Depending on the type of driving and electrical load it usually takes from 10-30 min of driving and then you will see it drop down as the battery comes up to voltage. The alt in fact is always throttling up and down as electrical load or accessory demands change, it's pretty normal. If in doubt simply use a voltmeter and measure across the battery when it's running. It should read anywhere from 13-14.5 volts depending on the battery state of charge.

2_point8_boy

ok, determined that the change on my insturment voltmeter is normal. Now, does anyone know for sure what the wire under the center console is. I describe it in my first question at the top. Thanks.