From rec.autos.makers.chrysler.. Ping DS and tell him thanks !!

----- Original Message -----
From: "Daniel J. Stern" >
Newsgroups: sci.electronics.misc,alt.autos.gm,rec.autos.makers .chrysler
Sent: Friday, November 19, 2004 1:14 PM
Subject: alternator circuit question


> On Fri, 19 Nov 2004, Jon G. wrote:
>
>> I have a 91 Plymouth Acclaim, and the alternator doesn't charge the
>> battery. I took the alternator out and had it tested, and there's
>> nothing wrong with it. I put a new battery in it, but it still won't
>> charge. I checked the fuseable link from the alternator to the battery,
>> and there is continuity. Therefore, it must be the computer.
>
> The regulator is a part of the Single Board Engine Controller, yes.
>
>> there are 4 connections on the alternator
>
>> L1: direct to battery, positive
>> L2: direct to battery, negative
>> c1: small wire, logic, to computer, activates diode
>> c2: small wire, logic, to computer, also battery ground.
>
> What you are calling "logic" wires are the field wires.
>
>> I want to activate the alternator continuously and put on an
>> external voltage regulator.
>
> <etc>
>
> The way you plan to do it will not work.
>
> Here is a fix that *will* work, without replacing the engine computer and
> without causing any additional problems:
>
> First, pick one of the following regulators:
>
> Regular normal electromechanical regulator:
> NAPA Echlin VR32
>
> Extra heavy duty electromechanical regulator w/vibrationproof mount:
> NAPA Echlin VR34
>
> Extra heavy duty electromechanical regulator w/vibrationproof mount and
> convenient external voltage adjustment screw:
> NAPA Echlin VR35, Standard-Bluestreak VR106
>
> Transistorized regulator with no moving parts (no adjusting screw):
> Standard-Bluestreak VR101, Wells VR706 (the wells item is very
> inexpensive; it works but Wells doesn't make my favourite stuff)
>
> Waterproof potted IC regulator with no moving parts (no adjusting screw):
> NAPA Echlin VR1001, Standard-Bluestreak VR128
>
>
> Any of these regulators will have two terminals on it, one marked "IGN"
> and the other marked "FLD". (the VR1001 and VR128 have the "fld" terminal
> on the end of a short wire lead). The alternator gets the original C1 and
> C2 wires removed from its two field terminals (right next to each other,
> small studs with nuts retaining the two flag terminals).
>
> The regulator IGN terminal gets 12V via the ignition switch, and the "FLD"
> terminal gets connected via a wire to one (either) of the field terminals
> on the alternator. The other field terminal on the alternator gets
> connected via a wire to ground. Run a ground wire -- 16ga is plenty --
> between the regulator base and the battery negative terminal, and mount
> the regulator such that it won't rock 'n' roll around. At this point, your
> charging system will once again work fine. If you got the adjustable
> regulator, set it for 14.2v across the battery with the engine fully
> warmed up and ambient temperature above 50F.
>
> If your "Check Engine" light comes on, put a resistor across the two
> original field wires C1 and C2 before securing these wires such that they
> can't ground out or get caught in any moving parts.
>
> Close the hood; you're done.