Dodge RAM TRUCK 1500 1995 Service Manual page 386

B R IGNITION SYSTEMS 8D -13
IGNITION COIL RESISTANCE—EXCEPT 8.0L V-10 ENGINE
COIL ( M A N U F A C T U R E ! )
P R I M A R Y R E S I S T A N C E
2 1 - 2 7 ° C ( 7 0 - 8 0 ° F )
S E C O N D A R Y R E S I S T A N C E
2 1 - 2 7 ° C ( 7 © - 8 0 ° F )
Diamond
0.97- 1.18 Ohms
11,300- 15,300 Ohms
Toyodenso
0.95- 1.20 Ohms
11,300- 13,300 Ohms
refer to the appropriate Powertrain Diagnostics Pro­
cedures 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. 11). 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.
ENGINE
C Y L I N D E R ^
NUMBER
COIL
"MOUNTING 5
BOLTS (8)
J948D-6
Fig. 11 Ignition Coil Packs—8.0L V-10 Engine
To test the secondary resistance of each individual
paired coil, attach an ohmmeter across the coil tow­
ers (Figs. 12 or 13). This must be done between cor­
responding cylinders number 3/2, 7/4, 1/6, 9/8 or 5/10
(Fig. 11). Refer to figure 16 for resistance specifica­
tions.
To test the primary resistance of the front coil
pack, attach an ohmmeter between the B+ coil termi­
nal and either the right (cylinders 3/2), center (cylin­
ders 7/4) or left coil (cylinders 1/6) terminals (Fig.
14). Refer to figure 16 for resistance specifications.
To test the primary resistance of the rear coil pack,
attach an ohmmeter between the B+ coil terminal
J918D-2
and either the right (cylinders 9/8) or left (cylinders
5/10) coil terminals (Fig. 15). Refer to figure 16 for
resistance specifications.
OHMMETER
MAKE OHMMETER
CONNECTIONS AT
CORRESPONDING CYLINDERS
(1/6, 7/4 OR 3/2).
FRONT
OF
ENGINE
J948D-14
Fig. 12 Checking Coil Secondary Resistance—Front
Coils—8.0L V-10 Engine
IGNITION CONTROL MODULE TEST—8.0L V-10
ENGINE
The ICM is located in the engine compartment. It
is mounted to the right inner fender behind the cool­
ant reserve/overflow tank.
Ignition coil ground path circuits for paired cylin­
ders number 1/6, 3/2 and 9/8 are operated by the
PCM only.
A separate ignition control module (ICM) (Fig. 17),
along with commands from the PCM, is used to con­
trol the ground path circuits for only two of the five
paired coil packs. This will be for paired cylinders
number 4/7 and 5/10.
For ICM testing, refer to the appropriate Power-
train Diagnostic Procedures manual for operation of
the DRB scan tool.