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.

will that still set a fault for alt not switching properly?, If you bypass
the alt field in the PCM?
"Daniel J. Stern" > wrote in message
n.umich.edu...
> 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.

will that still set a fault for alt not switching properly?, If you bypass
the alt field in the PCM?
"Daniel J. Stern" > wrote in message
n.umich.edu...
> 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.

On Fri, 19 Nov 2004, maxpower wrote:

> will that still set a fault for alt not switching properly?

Some SBEC calibrations won't care that an external regulator is doing the
job; others will set a fault. Of those that set a fault, some (mostly
'92-up) will illuminate the MIL. This can be worked around as previously
mentioned by putting a resistor across the vehicle's two original field
wires (which have been disconnected from the alternator). And really,
that's the only thing that matters, is that this repair be made in such a
manner as not to have the Check Engine light on. If it sets a fault code,
who cares? There are plenty of cases where an irrelevant fault is stored.
Cars without A/C routinely set a 33 ("Open or Short in A/C clutch
circuit"). K-car derivatives that have had the torque converter lockup
disconnected in accordance with the TSB on part-throttle surge and lug
will set a 37 ("Open or short in TCC circuit").

The important thing is that the charging system's operation will be
reliably restored without causing new problems, and at a much lower cost
than replacing the computer.

DS

On Fri, 19 Nov 2004, maxpower wrote:

> will that still set a fault for alt not switching properly?

Some SBEC calibrations won't care that an external regulator is doing the
job; others will set a fault. Of those that set a fault, some (mostly
'92-up) will illuminate the MIL. This can be worked around as previously
mentioned by putting a resistor across the vehicle's two original field
wires (which have been disconnected from the alternator). And really,
that's the only thing that matters, is that this repair be made in such a
manner as not to have the Check Engine light on. If it sets a fault code,
who cares? There are plenty of cases where an irrelevant fault is stored.
Cars without A/C routinely set a 33 ("Open or Short in A/C clutch
circuit"). K-car derivatives that have had the torque converter lockup
disconnected in accordance with the TSB on part-throttle surge and lug
will set a 37 ("Open or short in TCC circuit").

The important thing is that the charging system's operation will be
reliably restored without causing new problems, and at a much lower cost
than replacing the computer.

DS

Thank you DS..

I have now saved it in another place where I won't lose it !!!

Ted

Thank you DS..

I have now saved it in another place where I won't lose it !!!

Ted

On Fri, 19 Nov 2004, me! wrote:

> Thank you DS..
>
> I have now saved it in another place where I won't lose it !!!

Glad to help (and this one posted today contained a much more complete
list of usable regulators).

On Fri, 19 Nov 2004, me! wrote:

> Thank you DS..
>
> I have now saved it in another place where I won't lose it !!!

Glad to help (and this one posted today contained a much more complete
list of usable regulators).

the reason why i ask is because the emiision test center cares here in MD.
I no all about those irrelvant codes, its hard to tell the emission test
center that the check engine lite is on becuase of a P/s switch is faulty,
but they dot care, they go by the guidelines, lite is on vehicle fails
"Daniel J. Stern" > wrote in message
n.umich.edu...
> On Fri, 19 Nov 2004, maxpower wrote:
>
> > will that still set a fault for alt not switching properly?
>
> Some SBEC calibrations won't care that an external regulator is doing the
> job; others will set a fault. Of those that set a fault, some (mostly
> '92-up) will illuminate the MIL. This can be worked around as previously
> mentioned by putting a resistor across the vehicle's two original field
> wires (which have been disconnected from the alternator). And really,
> that's the only thing that matters, is that this repair be made in such a
> manner as not to have the Check Engine light on. If it sets a fault code,
> who cares? There are plenty of cases where an irrelevant fault is stored.
> Cars without A/C routinely set a 33 ("Open or Short in A/C clutch
> circuit"). K-car derivatives that have had the torque converter lockup
> disconnected in accordance with the TSB on part-throttle surge and lug
> will set a 37 ("Open or short in TCC circuit").
>
> The important thing is that the charging system's operation will be
> reliably restored without causing new problems, and at a much lower cost
> than replacing the computer.
>
> DS