Dodge ram truck 3500 1996 Service Manual page 369

BR
JllKIiNG SYSTEMS 8B - 7
DIAGNOSIS AND TESTING (Continued)
and 30. I f OK, see the Relay Circuit Test In this
group. I f not OK, replace the faulty relay.
RELAY TERMINALS
87A
RELAY CAVITIES
87
85
| 87A j
86
30
J958A-2
TERMINAL LEGEND
NUMBER i IDENTIFICATION
30 C O M M O N FEED
85 COIL GROUND
8 6 COIL BATTERY
8 7 NORMALLY OPEN
87A NORMALLY CLOSED
Starter Relay
RELAY CIRCUIT
TEST
(1) The relay common feed terminal cavity (30) is
connected to battery voltage and should be hot at all
times. I f OK, go to Step 2. I f not OK, repair the open
circuit to the PDC fuse as required,,
(2) The relay normally closed terminal (87A) is
connected to terminal 30 In the de-energized position,
but is not used for this application. Go to Step 3.
(3) The relay normally open terminal (87) Is con­
nected to the common feed terminal (30) In the ener­
gized position. This terminal supplies battery voltage
to the starter solenoid field coils. There should be
continuity between the cavity for relay terminal 87
and the starter solenoid terminal at all times. I f OK,
go to Step 4. I f not OK, repair the open circuit to the
starter solenoid as required.
(4) The coil battery terminal (86) is connected to
the electromagnet in the relay. I t is energized when
the Ignition switch is held In the Start position. On
vehicles with a manual transmission, the clutch
pedal must be fully depressed for this test. Check for
battery voltage at the cavity for relay terminal 86
with the ignition switch in the Start position, and no
voltage when the ignition switch is released to the
On position. I f OK, go to Step 5. I f not OK with an
automatic transmission, check for an open or short
circuit to the ignition switch and repair, i f required.
I f the circuit to the Ignition switch is OK, see the
Ignition Switch Test in this group. I f not OK with a
manual transmission, check the circuit between the
relay and the clutch pedal position switch for an
open or a short. I f the circuit is OK, see the Clutch
Pedal Position Switch Test in this group.
(5) The coil ground terminal (85) is connected to the
electromagnet in the relay. On vehicles with an auto­
matic transmission, it is grounded through the park/
neutral position switch only when the gearshift selector
lever is in the Park or Neutral positions. On vehicles
with a manual transmission, it is grounded at all times.
Check for continuity to ground at the cavity for relay
terminal 85. I f not OK with an automatic transmission,
check for an open or short circuit to the park/neutral
position switch and repair, i f required. I f the circuit is
OK, see the Park/Neutral Position Switch Test in this
group. I f not OK with a manual transmission, repair
the circuit to ground as required.
PARK/NEUTRAL
POSITION SWITCH TEST
(1) Place the transmission gear selector lever in
the Park position.
(2) Disconnect and isolate the battery negative
cable.
(3) Raise and support the vehicle.
(4) Disconnect the park/neutral position switch
harness connector.
(5) Check for continuity between the center switch
terminal and a good chassis ground. There should be
continuity. I f OK, go to Step 6. I f not OK, replace the
faulty switch.
(6) Move the transmission gear selector lever to
the Reverse position and check ' for continuity
between the center switch terminal and a good chas­
sis ground. There should be no continuity. I f not OK,
replace the faulty switch.
CLUTCH PEDAL POSITION SWITCH TEST
The clutch pedal position switch is integral to the
clutch pedal pushrod. I t is located near the dash
panel under the instrument panel. The harness con­
nector for the switch is wrapped with foam tape.
(1) Disconnect and isolate the battery negative
cable.
(2) Disconnect the switch harness connector.
(3) Check for continuity between the two cavities in
the switch-half of the harness connector with the clutch
pedal released. There should be no continuity. I f OK, go
to Step 4. I f not OK, replace the faulty switch.
(4) Check for continuity between the two cavities
in the switch-half of the harness connector again
with the clutch pedal depressed. There should now be
continuity. I f OK, see the Ignition Switch Test in this
group. I f not OK, replace the faulty switch.
IGNITION SWITCH TEST
WARNING: ON VEHICLES EQUIPPED WITH AN AIR-
BAG, REFER TO GROUP 8M - PASSIVE RESTRAINT
SYSTEMS BEFORE ATTEMPTING STEERING
WHEEL OR STEERING COLUMN COMPONENT
DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI­
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.