'95 YJ alternator(?)problem

OK, so I'm driving to work. Cruising along, not a care in the world
at about 60mph. All of a sudden the Check Engine light comes on.
Upon looking at the gauges, I discover that the dash lights are dim
and the volt gauge shows that the alternator is not charging.
Just from habit, I push in the clutch and rev the engine. The volt
gauge goes back to 14.5v and the dash lights get bright again. Of
course the CE light stays on. Continued on towards home and this
repeats itself a couple of times and then, the last 30 miles were
trouble free.
Got home and checked the codes. The only one I got that was new was a
41(or maybe 42, I've slept since last night). "alt field open or
shorted"
Now, I heard a nasty rumour that DC put the voltage reg in the 'puter
on these Jeeps and not in the alt., although my book(a Chilton's)says
different.
Am I looking at a wiring problem or possible failure of the alternator
or ECM? I know it would be a lot easier to diagnose if it'd quit
altogether, but I'd rather not have to go through the "dead on the
side of the road" stage, as the weather around here is supposed to
turn nasty and I've still got the 135 mile round trip to work to do
every day until Friday.
Oh, and what's with the damned thing throwing an a/c clutch relay
code, when it doesn't and never did have a/c?
--
Old Crow
'82 Shovelhead FLTC 92" 'Pearl'
'95 Jeep Wrangler YJ
TOMKAT, BS#133, SENS, MAMBM, DOF#51, SPONGER#2

Old Crow did pass the time by typing:

> Got home and checked the codes. The only one I got that was new was a
> 41(or maybe 42, I've slept since last night). "alt field open or
> shorted"

Loose/dirty connection probably

> Now, I heard a nasty rumour that DC put the voltage reg in the 'puter
> on these Jeeps and not in the alt., although my book(a Chilton's)says
> different.

On the ZJs at least it's part of the ECU. But with what your describing
I'd check for loose connections first. Last time I had that problem I gave
the battery cable a tug and it popped out.

> Oh, and what's with the damned thing throwing an a/c clutch relay
> code, when it doesn't and never did have a/c?

The A/C fault code on a non A/C equipped vehicle is normal. It's always
there, just won't turn the CE light on.

--
DougW

On Tue, 21 Dec 2004 06:30:58 -0600, "DougW"
> wrote:

>Old Crow did pass the time by typing:
>
>> Got home and checked the codes. The only one I got that was new was a
>> 41(or maybe 42, I've slept since last night). "alt field open or
>> shorted"
>
>Loose/dirty connection probably
>
>> Now, I heard a nasty rumour that DC put the voltage reg in the 'puter
>> on these Jeeps and not in the alt., although my book(a Chilton's)says
>> different.
>
>On the ZJs at least it's part of the ECU. But with what your describing
>I'd check for loose connections first. Last time I had that problem I gave
>the battery cable a tug and it popped out.

Well, due to our snowstorm, I had time over the holidays to look at
the damned thing.
Took the connections at the alt loose, sanded them and re-installed
the alt, also set the belt a bit tighter than it had been.
Took the battery loose(actually the first step<g.), and cleaned all
the connections. Drove over to a friend's house last night(80 mile
round trip)and got home without the alternator doing anything funny.
So maybe it's fixed. I'll be more confident tonight after I get home
from work, as I really didn't see anything amiss while I was fussing
with it.

--
Old Crow
'82 Shovelhead FLTC 92" 'Pearl'
'95 Jeep Wrangler YJ
TOMKAT, BS#133, SENS, MAMBM, DOF#51, SPONGER#2

Old Crow wrote:

> On Tue, 21 Dec 2004 06:30:58 -0600, "DougW"
> > wrote:
>
>
>>Old Crow did pass the time by typing:
>>
>>
>>>Got home and checked the codes. The only one I got that was new was a
>>>41(or maybe 42, I've slept since last night). "alt field open or
>>>shorted"
>>
>>Loose/dirty connection probably
>>
>>
>>>Now, I heard a nasty rumour that DC put the voltage reg in the 'puter
>>>on these Jeeps and not in the alt., although my book(a Chilton's)says
>>>different.
>>
>>On the ZJs at least it's part of the ECU. But with what your describing
>>I'd check for loose connections first. Last time I had that problem I gave
>>the battery cable a tug and it popped out.
>
>
> Well, due to our snowstorm, I had time over the holidays to look at
> the damned thing.
> Took the connections at the alt loose, sanded them and re-installed
> the alt, also set the belt a bit tighter than it had been.
> Took the battery loose(actually the first step<g.), and cleaned all
> the connections. Drove over to a friend's house last night(80 mile
> round trip)and got home without the alternator doing anything funny.
> So maybe it's fixed. I'll be more confident tonight after I get home
> from work, as I really didn't see anything amiss while I was fussing
> with it.
>
> --
> Old Crow
> '82 Shovelhead FLTC 92" 'Pearl'
> '95 Jeep Wrangler YJ
> TOMKAT, BS#133, SENS, MAMBM, DOF#51, SPONGER#2

ok, i just had this problem in my 93 yj. last
monday night was barely over 0 degrees. the next
morning, still only 2 degrees. i noticed i was
getting no charging at all. about 10 minutes after
starting, then my charge came back. it hasn't
happened since (temps were over 25 all week).
tonight is going to be around 0 again, i will see
what happens.

--
Ben Jerew
ASE Master Technician
New Country Lexus of Latham, NY
Amateur Off-Roader

MudPuppy76 did pass the time by typing:

> ok, i just had this problem in my 93 yj. last
> monday night was barely over 0 degrees. the next
> morning, still only 2 degrees. i noticed i was
> getting no charging at all. about 10 minutes after
> starting, then my charge came back. it hasn't
> happened since (temps were over 25 all week).
> tonight is going to be around 0 again, i will see
> what happens.

Odds are the same thing. A low or no charge.
Check your battery fluid, sounds like your battery
is freezing up or a cell is going dry.

Could also be your battery is old. Cold kills
weak batteries.

Gets too cold you migh have to do what my dad did
up in montanna. Take the battery inside over night.
They make thermal blankets for batteries, and heaters.

--
DougW

DougW wrote:

> MudPuppy76 did pass the time by typing:
>
>
>>ok, i just had this problem in my 93 yj. last
>>monday night was barely over 0 degrees. the next
>>morning, still only 2 degrees. i noticed i was
>>getting no charging at all. about 10 minutes after
>>starting, then my charge came back. it hasn't
>>happened since (temps were over 25 all week).
>>tonight is going to be around 0 again, i will see
>>what happens.
>
>
> Odds are the same thing. A low or no charge.
> Check your battery fluid, sounds like your battery
> is freezing up or a cell is going dry.
>
> Could also be your battery is old. Cold kills
> weak batteries.
>
> Gets too cold you migh have to do what my dad did
> up in montanna. Take the battery inside over night.
> They make thermal blankets for batteries, and heaters.
>
i'll check tomorrow when i get to the shop. pull
out that battery acid tester (gathering dust)

--
Ben Jerew
ASE Master Technician
New Country Lexus of Latham, NY
Amateur Off-Roader

On Tue, 28 Dec 2004 00:43:08 GMT, "MudPuppy76
<\"<moc.rr.pacyn\"@\"pupralop\">" <--SDRAWKCAB> wrote:

>Old Crow wrote:
>
>> On Tue, 21 Dec 2004 06:30:58 -0600, "DougW"
>> > wrote:
>>
>>
>>>Old Crow did pass the time by typing:
>>>
>>>
>>>>Got home and checked the codes. The only one I got that was new was a
>>>>41(or maybe 42, I've slept since last night). "alt field open or
>>>>shorted"
>>>
>>>Loose/dirty connection probably
>>>
>>>
>>>>Now, I heard a nasty rumour that DC put the voltage reg in the 'puter
>>>>on these Jeeps and not in the alt., although my book(a Chilton's)says
>>>>different.
>>>
>>>On the ZJs at least it's part of the ECU. But with what your describing
>>>I'd check for loose connections first. Last time I had that problem I gave
>>>the battery cable a tug and it popped out.
>>
>>
>> Well, due to our snowstorm, I had time over the holidays to look at
>> the damned thing.
>> Took the connections at the alt loose, sanded them and re-installed
>> the alt, also set the belt a bit tighter than it had been.
>> Took the battery loose(actually the first step<g.), and cleaned all
>> the connections. Drove over to a friend's house last night(80 mile
>> round trip)and got home without the alternator doing anything funny.
>> So maybe it's fixed. I'll be more confident tonight after I get home
>> from work, as I really didn't see anything amiss while I was fussing
>> with it.
>>
>> --
>> Old Crow
>> '82 Shovelhead FLTC 92" 'Pearl'
>> '95 Jeep Wrangler YJ
>> TOMKAT, BS#133, SENS, MAMBM, DOF#51, SPONGER#2
>
>ok, i just had this problem in my 93 yj. last
>monday night was barely over 0 degrees. the next
>morning, still only 2 degrees. i noticed i was
>getting no charging at all. about 10 minutes after
>starting, then my charge came back. it hasn't
>happened since (temps were over 25 all week).
>tonight is going to be around 0 again, i will see
>what happens.

Well, I did my 133 mile commute yesterday with no porblem...I'm saying
it's fixed...for now.
I suppose if I convert this thing to a 'real' GM one wire alternator,
I'll have to pull the bulb out of the check enging light or get used
to looking at it :-)
--
Old Crow
'82 Shovelhead FLTC 92" 'Pearl'
'95 Jeep Wrangler YJ
TOMKAT, BS#133, SENS, MAMBM, DOF#51, SPONGER#2

"MudPuppy76 <\"" wrote:
>
> DougW wrote:
>
> > MudPuppy76 did pass the time by typing:
> >
> >
> >>ok, i just had this problem in my 93 yj. last
> >>monday night was barely over 0 degrees. the next
> >>morning, still only 2 degrees. i noticed i was
> >>getting no charging at all. about 10 minutes after
> >>starting, then my charge came back. it hasn't
> >>happened since (temps were over 25 all week).
> >>tonight is going to be around 0 again, i will see
> >>what happens.
> >
> >
> > Odds are the same thing. A low or no charge.
> > Check your battery fluid, sounds like your battery
> > is freezing up or a cell is going dry.
> >
> > Could also be your battery is old. Cold kills
> > weak batteries.
> >
> > Gets too cold you migh have to do what my dad did
> > up in montanna. Take the battery inside over night.
> > They make thermal blankets for batteries, and heaters.
> >
> i'll check tomorrow when i get to the shop. pull
> out that battery acid tester (gathering dust)
>
> --
> Ben Jerew
> ASE Master Technician
> New Country Lexus of Latham, NY
> Amateur Off-Roader

I see that lots because I off road. The mud or liquid sandpaper
polishes up my belts and they don't grab well when cold.

I test it with a cold off engine and see if I can hand slip the
alternator pulley. If I can hand slip it, it is dead or loose. The
alternator takes several HP to spin up under load and for sure if it
hand slips it won't charge fully if at all.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's