I have had 4 alternator and four new battery go dead the voltage reg on 3 of the altinators have tested bad changed battery conectors fuses and checked all the wires to and from altinator and battery the voltage didnt change or go down new starter we cant find out what is wrong is there something on my tracker killing the altinators please help

How old is the battery? In general, vehicle batteries are considered 'old' after 5 years especially on bigger engines.
Using a volt meter or a multimeter set to Volts try this. With the engine off and the Keys out test the voltage directly on the battery. You should get a reading somewhere around 12.6 to 13.2 volts. Start the engine and retest the battery voltage. If the alternator is working correctly the reading should rise to somewhere around 13.6 to 14.2 volts.

ok I have it. Had many VIT's (4 in fact once) before they bugged out of USA, a great car 4wd in snow, even deep.
2.7L V6 (H27)/?
you skipped step one in the ALTERNATOR swap
1: disconnect battery NEG LUG first. or bow the 100amp + ALT fuse.
called FUSE F1 under hood main fuse box.
thaT MAKES THE ALT 100 % DEAD.
XL7 CAR IS VERY different for normal Vitara's for sure.
the ALT has internal voltage REG so that is good news.
see it here. the real schematic, XL7 (02)
click me.

https://imgur.com/a/SkXBbfm








ALL








THE LAMP CHARGE MUST GLOW KEY ON OR LAMP IS BAD
OR f1 BLOWN, BOOM.
some brands of ALT use the charge lamp as bootstrap, self excitation path. (keep the lamp good and all is happy)
F1 is blown, BOOM ! doing it wrong.

Hi. There are four things to look at. One of the four will be the issue. Check for ground at the alternator. Check for battery power at the alternator's main (+) battery terminal. Check the field for 12volts (Key On). If these three tests pass you will need to remove the alternator and have it bench tested. This should help. Please let me know if you are still having an issue. Good Luck.

Some vehicles are fitted with a smart charging system that is designed to prevent the alternator charging during acceleration to free a few horsepower to help.

My experience of these is very limited but there is an ECU that controls them and the battery, charging or ignition light using information from the engine management system.
The alternator generally has an extra plug with about four or five wires which when disconnected render the alternator a standard machine sensed type.

Japanese vehicles used separate voltage regulators longer than most types. You either need experience or a wiring diagram for good fault diagnosis but mostly it is unnecessary to check the charging current of an alternator which bears little significance unless being tested with a graduated load or adjustable carbon pile.

The current output of a healthy alternator is dependent on the terminal voltage of the battery which in turn is dependent on the electrical load placed upon it. Switching on the lights should lower the voltage and increase the alternator output. If the battery is particularly good the voltage won't fall very much and the current won't increase as much as expected...

Measuring the battery voltage with the engine running at about 2000/2500 rpm is sufficient for most purposes. With nothing switched on and a fully charged battery it should be around 14.5 volts and with everything switched on (lights, HRW, heater fan, etc.) a healthy alternator should continue to maintain a voltage above that of a healthy fully charged battery (13.2 volts).

If the voltage isn't maintained on load the charging system, probably the alternator, is faulty and should be independently tested.

17v on is bad. its too high.
are you using a good voltmeter. a DMM, ? or relic analog meter.?
you put a new alternator in the car? not from autozoned i hope.
the wiring to the Alternator must be all good, them includes the case ground and battery cables, end to end, good and tight and not corroded.
the regulator is inside your ALT>
the ALT has 5 connections 1 is ground. any bad, reg can go nuts.
newer cars , go less nuts. they detect more errors and shut down
your is overcharging and will burn a battery up in no time.(heat)
wire:
Grounds good.
idiot lamp ,must be there, an working or alt may start up dead.
the lamp creates excitation currents, to boot up ALT.
wire B, goes to battery via fuse link, if this big wire fails. all bets off.
wire IG goes to 7.5A gage fuse, it must not be blown.
wire S, (sense) is 5amp ALT-s fuse, this senses battery voltage
if this wire drops in voltage the ALT will go to max. (or shut down)
toss coin there, lots of regs sub'd out in so many years, and rebuilts.

the regulator is not working right.
that means 3 things.
1: reg is bad.
2: reg is being lied to. (bad wires) even bad battery.

did you really check all fuses. (using an ohmmeter)
what engine, I4 or V6?????
are you posting to someone elses PCM Com problem or what?
is this just and alternator issue , how confusing can this be....
PCM> coms. fails.
3 possible.
1: pin 16 in the OBD2 conn, is not 12vdc. blown fuse. (use a voltmeter)
2: wrong scan tool old tool , on modern CAN buss car will fail. 100%
dead. (open SCAN tool book read if it supports CAN buss)
3: Dead PCM or id bet its , a fuse blown to it.

now i do ALT.
18v is bad. (using a quality DMM or radio shack 1960 meter?)
it means the ALT regulator OUT of CONTROL. ( or bad wiring to it)
changed what?, alt is new, used, rebuilt, barrowed? what.?
This car , im looking it up now, at alldata.com so could you,
or the FSM.

this ALT has a regulator, but is just a slave to the PCM.
in that the PCM controls the REG with 3 wires.
the diagnosis is not easy , i recommend, the FSM
it covers all steps., in the diagnosis,

top fail reasons.
1: bad fuses.
2: bad wiring and connections. (see schematic)
3: bad battery (not you) (open cells cause REG to shut down. )
4: bad ALT. (i say a fella change alt 5 times, and skipped #2)
5: bad PCM. (last, , show me that tests, in FSM)

all that and tons more in the FSM. read it.


or log in to alldata.com and read the Charging pages.

stock car YJ ? , or all hacked up. (old cars get hacked)
2.5 or 4.0 liter engine? still have a real jeep alternator not upgraded?

loss of electrical power (first rule, we never need to guess.!!!)
not with a voltmeter. (tool that costs $20 )
alternator good (by what means, autozoned?) ( we can find out one car)
but low on gauge. what gauge in dash voltmeter.? sure...
i think you car has no charge lamp only the dash VM.

own an volt meter? a DMM? hand volt meter?

1: if the alternator charge lamp is stuck on driving.
2: is battery voltage at 13.3 to 15vdc with engine at 800 RPM idling
alternator belt not slipping, for sure.....???
if the battery voltage is near 12.5v and falling running that is
an Alternator system failure, note i said, system. !!!

this is first. if we get to here. we can find the real cause.
test 3:
is the charge lamp on keyon, and goes out running?
make sure the big fuse for the alternator in the engine bay fuse
box is not blown, 50amp?

I have no 95 FSM and my online source sucks for 95

Alternator dead: (alt good)
1: belt slipping . engine at 300rpm, nah.
2: fuse blown, the big one. (engine bay fuse box)
3: ;wrong alternator, there are many, most others will fail, even good ones.......
4: alternator ground bad. (end to end, to battery minus)
5: bad wiring to same. bad connections, any to battery or alt.
6: some jeeps the PCM has the field regulator, see link below.
ECU pin 20 , is field pin, it is on 95, 4.0L (engine not stated)

is the CEL lamp on, and throwing code 41 DTC?, alt, field errors?

the alt has 4 pins, battery, field,ground and voltage sense.
The reg is in the PCM. and if bad is a bad $3 transistor..
see same form for fix for that issue..

i think this is same as your. 1996 is big change year.
http://www.jeepforum.com/forum/f12/1993-wrangler-pcm-ecu-ecm-pin-out-diagram-1170004/


you can test the alt, PCM wire pulled !, by full fielding the alt.
grounding the field term, no wires on field pin of alt.
see FSM for details on that.
The PCM modulates the field pin to control charge at all times.

The voltage regulator it in the ECM.What you need to do is go to the basic which can be overlooked like is the Alternator fuse burnt open that will require a new fuse, how is the battery terminal connection? You need to check that,Or how is the calbe from the alternator to the Battery is the connection in good shape? Those you need to check you mainly need a voltmeter to do this but a good visual inspection can get results,

There's no reset for battery light, when problem is fix the light will go off, light still on could be a defective alternator or a fuse could be bad, have the alternator check first could be bad, if it testes good look for bad fuse.

Change voltage regulator. Does the battery take a charge from a charger? If not, replace battery. If it does, then regulator is faulty. If still nothing, return alternator to place of purchase, and have it checked.