My alternator is not charging on my 1987 buick regal. I think the dark brown wire is suppose to be hot when the key is on but i have no power there. The red one has 12 volts and i know that is just tied into the hot coming off the starter. I tried tracing it back under the dash but have no clue where is goes? Anybody got some advice or a wiring diagram before i have to tear my buick apart. Thanks.
alternator dark brown wire
- Thread starter Dmax Cody
- Start date
- Status
its not power in. its a ground from the ign switch.you have a thick B+ on a 1/4 inch stud on the back, the brown wire is the ground from the ign switch while the red wire is to power the internal voltage regulator.
Is the gen light on with the motor off and key in "run"? If it's not, bulb is burnt and thus, no field current and no charging. If bulb is good, check for open circuit in brown wire.
Well all this makes sense. I pulled the bulb out after i put the new motor in because i went to a auto meter volt gauge. So if i put the bulb back in hopefully it will work. That really seems like a bad ideal if the bulb ever did burn out then the car wouldnt charge. Also for sure it is a negative ground and not keyed ignition power?
It's only a ground if the generator is shorted to ground, or putting out less than battery voltage. Then current flows and bulb lights. When generator is putting out battery voltage or better, bulb "sees" positive current from both sides and goes out.
Ok but what is the simple set up then? Can 12 volt keyed ignition power be put to the brown wire to tell the alternator to charge? My other g body is a 1987 monte circle track car that im building. Im wiring the car right now. No dash or factory wiring harness but will be running an alternator. I had it running on saturday and put power to the brown wire and had my meter on the battery and it started charging. Im not gutting my regal but just trying to understand how this does work. Thanks
I'm no electronics whiz but you would think so. Cars with gauges use the choke heater relay to alert the driver that the alt is out. Unlike a generator, the alternator needs outside current to excite the field windings(brown wire, terminal 1). Then the other wire (red on newer or blue on older cars) in the alt harness connector is connected to a central point in the car's wiring to get an accurate indication of the electrical load on the system(terminal 2).
I dont mean to thread jack but i'm having problems with my alternator also. Could you guys check this thread & help me out, Thanks
http://gbodyforum.com/viewtopic.php?f=5&t=22069
http://gbodyforum.com/viewtopic.php?f=5&t=22069
Monte Olrac and Pontiacgp showed the correct hook ups. Basically, the "batt" terminal with the nut gets a heavy gauge wire direct to the battery +. That is your charging line. The field (brown) goes to the idiot light or gauge, or choke heater relay depending on model. The other red wire should not be connected to the "batt" terminal allthough many do it out of convenience. It needs to go to where all your red + wires congregate like the fusible link by the starter, or sometimes there's a big soldered junction wrapped in tape in the harness that is on the intake manifold. This senses the draw on the system and the regulator uses that to adjust the alternator to the car's needs.
- Status
Similar threads
