Stator Windings Continuity Test; Stator Internal Short Circuit Test; Diode Trio Short Circuit Test; Test With Diode Trio Removed - Jeep J-10 Series 1982 Technical & Service Manual

Stator Windings Continuity Tost
NOTE: The optional 70 and 85 amp alternators (Deko
15-SI) have delta wound stator windings that cannot be
tested for open windings with an ohmmeter or test
lamp. However, if the results of all other tests are nor
mal and the alternator fails to supply the rated output,
open stator windings are probable.
To perform this test, remove the stator and rear hous
ing assembly from the rotor and front housing assem
bly. Refer to Alternator Overhaul for procedure. An
ohmmeter set for the xl scale is used to perform the test.
Touch ohmmeter lead probes to any two stator wind
ings and note the resistance (fig. 1E-8). Test all the
stator windings in this manner. Equal indications
should be obtained for each pair of windings tested.
OHMMETER
70159
Fig. 1E-8 Stator Windings Continuity Test
Test Results
An infinite resistance (no pointer movement) in
dicates an open winding. Inspect the neutral junction
splice for a poor solder connection. Resolder the con
nection even if it appears to be good. Retest the continu
ity. If an open still exists, replace the stator windings.
An indication of more than 1 ohm indicates a possible
cold solder joint. Inspect the neutral junction splice and
resolder if necessary.
Stator Internal Short Circuit Test
An internal short (e.g., between adjacent windings) is
difficult to locate without laboratory test equipment. If
all other electrical checks are normal and the alternator
fails to supply the rated output, shorted stator windings
are probable.
Diode Trio Short Circuit Test
The diode trio is tested in two ways: when installed in
the rear housing and when removed from the rear
housing.
CHARGING SYSTEM 1E-9
CAUTION: Do not use high voltage, such as a 110-volt
test lamp, to test the diode trio.
Test with Diode Trio Installed
(1) Before removing diode trio, connect ohmmeter,
with lowest range scale selected, from brush lead clip to
rear housing (fig. IE-!)) and note resistance.
(2) Reverse test lead probe connections. If both in
dications are zero, inspect for grounded brush lead clip
caused by absence of insulating washer, absence of in
sulating sleeve over screw, or damaged insulation (fig.
1E-1-1).
CJ) Remove screws to inspect washers and sleeves.
If screw assembly is correct and both ohmmeter obser
vations are same, replace voltage regulator.
Test with Diode Trio Removed
(1) Remove diode trio from rear housing assembly.
(2) Connect ohmmeter having 1-1/2 volt cell to
brush terminal and one stator winding terminal (fig. 1E-
10). Observe resistance on lowest range scale.
i'.i) Reverse probes at same two terminals.
(4) Replace diode trio if both resistances are identi
cal. Good diode trio will give one high and one low
resistance.
INSULATING
WASHERS
BRIDGE
RECTIFIER
OHMMETER
ATTACHING
NUTS
Fig. 1E-9 R?ar ihnsina Assfimtiiy
OHMMETER
DIODE
TRIO
70160