Dodge ram truck 3500 1996 Service Manual page 390

8D - 8 IGNITION SYSTEM •
DIAGNOSIS AND TESTING (Continued)
der head or block while rotating the engine with the
starter motor. Observe the spark plug cable terminal
for an arc. I f steady arcing occurs, i t can be expected
that the ignition secondary system is operating cor­
rectly ( I f the i g n i t i o n coil cable is removed for
this test, instead of a spark p l u g cable, the
spark intensity w i l l be m u c h higher). I f steady
arcing occurs at the spark plug cables, but the engine
will not start,' connect the DRB scan tool. Refer to
the appropriate Powertrain Diagnostic Procedures
service manual.
IGNITION COIL TEST—3.9L/5.2L/5.9L ENGINES
To perform a complete test of the ignition coil and
its circuitry, refer to the DRB scan tool. Also refer to
the appropriate Powertrain Diagnostics Procedures
manual. To test the coil only, refer to the following:
The ignition coil (Fig. 13) is designed to operate
without an external ballast resistor.
Fig. 13 ignition Coii (5.2L Shown)
Inspect the ignition coil for arcing. Test the coil
according to coil tester manufacturer's instructions.
Test the coil primary and secondary resistance.
Replace any coil that does not meet specifications.
Refer to the Ignition Coil Resistance chart.
B R
I f the ignition coil is being replaced, the secondary
spark plug cable must also be checked. Replace cable
if i t has been burned or damaged.
Arcing at the tower will carbonize the cable boot,
which i f i t is connected to a new ignition coil, will
cause the coil to fail.
I f the secondary coil cable shows any signs of dam­
age, i t should be replaced with a new cable and new
terminal. Carbon tracking on the old cable can cause
arcing and the failure of a new ignition coil. '
IGNITION COIL PACI TESTS—8 J L ¥-18 ENGINE
To perform a complete test of the ignition coil
packs and their circuitry, refer to the DRB scan tool.
Also refer to the appropriate Powertrain Diagnostics
Procedures manual. To test the coil packs only, refer
to the following procedure:
Two separate coil packs containing a total of five
independent coils are attached to a common mount­
ing bracket located above the right engine valve
cover (Fig. 14). The coil packs are not oil filled. The
front coil pack contains three independent epoxy
filled coils that will fire six cylinders. The rear coil
pack contains two independent epoxy filled coils that
will fire four cylinders.
Fig. 14 Ignition Coii Packs—8.0L V-10 Engine
C O I L (MANUFACTURER)
P R I M A R Y RESISTANCE
2 1 - 2 7 ° C ( 7 0 - 8 0 ° F )
S E C O N D A R Y RESISTANCE
2 1 - 2 7 ° C ( 7 § - 8 § ° P )
Diamond
0.97- 1.18 Ohms
11,300- 15,300 Ohms
Toyodenso
0.95- 1.20 Ohms
11,300- 13,300 Ohms
J918D-2
IGNITION COIL RESISTANCE