Charging System Resistance Tests; Current Output Test - Chrysler 1998 Viper RT/10 Owner's Manual

S R
CHARGING SYSTEM 8C - 3
D I A G N O S I S A N D T E S T I N G ( C o n t i n u e d )
nection at engine. They should all be clean and tight.
Repair as required.
CHARGING SYSTEM RESISTANCE TESTS
These tests w i l l show the amount of voltage drop
across the generator output wire, from the generator
output (B+) t e r m i n a l to the battery positive post.
They w i l l also show the amount of voltage drop from
the ground (-) t e r m i n a l on the generator to the bat-
tery negative post. A typical generator w i r i n g har-
ness is shown i n (Fig. 1). W i r i n g harness r o u t i n g as
shown i n (Fig. 1) may be slightly different depending
on vehicle model and/or engine. Refer to Group 8W,
W i r i n g Diagrams for additional information.
80b46bb1
Fig. 1 Generator Terminals-Typical
A voltmeter w i t h a 0-18 volt DC scale should be
used for these tests. By repositioning the voltmeter
test leads, the point of h i g h resistance (voltage drop)
can easily be found.
P R E P A R A T I O N
(1) Before starting test, make sure battery is i n
good condition and is fully-charged. See Group 8A,
Battery for more information.
(2) Check condition of battery cables at battery.
Clean i f necessary.
(3) Start the engine and allow i t to reach normal
operating temperature.
(4) Shut engine off.
(5) Connect an engine tachometer.
(6) F u l l y engage the p a r k i n g brake.
T E S T
(1) Start engine.
(2) Place heater blower i n h i g h position.
(3) T u r n on headlamps and place i n high-beam
position.
(4) T u r n vehicle interior lamps on.
(5) Start engine. B r i n g engine speed up to 2400
r p m and hold.
(6) Testing (+) circuitry:
(a) Touch the negative lead of voltmeter directly
to battery positive post.
(b) Touch the positive lead of voltmeter to the
B+ output terminal stud on the generator (not the
t e r m i n a l mounting n u t ) . Voltage should be no
higher t h a n 0.6 volts. I f voltage is higher t h a n 0.6
volts, touch test lead to t e r m i n a l m o u n t i n g stud
n u t and then to the w i r i n g connector. I f voltage is
now below 0.6 volts, look for dirty, loose or poor
connection at this point. Also check condition of the
generator output wire-to-battery bullet connector.
Refer to Group 8, W i r i n g for connector location. A
voltage drop test may be performed at each (+) con-
nection i n this circuit to locate the excessive resis-
tance.
(7) Testing (-) circuitry:
(a) Touch the negative lead of voltmeter directly
to battery negative post.
(b) Touch the positive lead of voltmeter to the
ground t e r m i n a l stud on the generator case (not
the t e r m i n a l mounting nut). Voltage should be no
higher t h a n 0.3 volts. I f voltage is higher t h a n 0.3
volts, touch test lead to t e r m i n a l m o u n t i n g stud
n u t and then to the w i r i n g connector. I f voltage is
now
below 0.3 volts, look for dirty, loose or poor
connection at this point. A voltage drop test may be
performed at each (-) connection i n this circuit to
locate the excessive resistance. This test can also
be performed between the generator case and the
engine. I f test voltage is higher t h a n 0.3 volts,
check for corrosion at generator m o u n t i n g points or
loose generator mounting.
CURRENT OUTPUT TEST
The current output test w i l l determine i f the
charging system can deliver its m i n i m u m test cur-
rent (amperage) output. Refer to the Specifications
section at the end of this group for m i n i m u m test
current (amperage) requirements.
The first part of this test (Test 1) w i l l determine
the combined amperage output of both the generator
and the E V R circuitry. The second part of this test
(Test 2) w i l l determine only generator amperage and
w i l l n o t include analysis of EVR circuitry. EVR cir-
cuitry is located w i t h i n the P C M . To test voltage reg-
ulator circuitry, refer to the appropriate Powertrain
Diagnostic Procedures service manual.