Content .. 70 71 72 73 ..

Chrysler 300M, Dodge Interpid. Manual - part 72

DIAGNOSIS AND TESTING - CONTROL
CIRCUIT TEST

The starter control circuit has:
• Starter motor with integral solenoid

• Starter relay

• Transmission range sensor, or Park/Neutral

Position switch with automatic transmissions

• Ignition switch

• Battery

• All related wiring and connections

• Powertrain Control Module (PCM)

CAUTION: Before performing any starter tests, the
ignition and fuel systems must be disabled.

• To disable ignition and fuel systems, disconnect

the Automatic Shutdown Relay (ASD). The ASD relay
is located in the Power Distribution Center (PDC).
Refer to the PDC cover for the proper relay location.

STARTER SOLENOID

WARNING: CHECK TO ENSURE THAT THE TRANS-
MISSION IS IN THE PARK POSITION WITH THE
PARKING BRAKE APPLIED.

(1) Verify battery condition. Battery must be in

good condition with a full charge before performing
any starter tests. Refer to Battery Tests.

(2) Perform Starter Solenoid test BEFORE per-

forming the starter relay test.

(3) Perform a visual inspection of the starter/

starter solenoid for corrosion, loose connections or
faulty wiring.

(4) Locate and remove the starter relay from the

Power Distribution Center (PDC). Refer to the PDC
label for relay identification and location.

(5) Connect a remote starter switch or a jumper

wire between the remote battery positive post and
terminal 87 of the starter relay connector.

(a) If engine cranks, starter/starter solenoid is

good. Go to the Starter Relay Test.

(b) If engine does not crank or solenoid chatters,

check wiring and connectors from starter relay to
starter solenoid and from the battery positive ter-
minal to starter post for loose or corroded connec-
tions. Particularly at starter terminals.

erly, trouble is within starter or starter mounted
solenoid, and replace starter. Inspect the ring gear
teeth.

STARTER RELAY

WARNING: CHECK TO ENSURE THAT THE TRANS-
MISSION IS IN THE PARK/NEUTRAL POSITION
WITH THE PARKING BRAKE APPLIED.

RELAY TEST

The starter relay is located in the Power Distribu-

tion Center (PDC) in the engine compartment. Refer
to the PDC label for relay identification and location.

Remove

the

starter

relay

from

the

PDC

described in this group to perform the following tests:

(1) A relay in the de-energized position should

have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 2. If not OK, replace the faulty relay.

(2) Resistance between terminals 85 and 86 (elec-

tromagnet) should be 75 ±5 ohms. If OK, go to Step
3. If not OK, replace the faulty relay.

(3) Connect a battery B+ lead to terminals 85 and

a ground lead to terminal 86 to energize the relay.
The relay should click. Also test for continuity
between terminals 30 and 87, and no continuity
between terminals 87A and 30. If OK, refer to Relay
Circuit Test procedure. If not OK, replace the faulty
relay.

Starter Relay Pinout

STARTING

8F - 25

STARTING (Continued)

CAV

FUNCTION

B (+)

IGNITION SWITCH OUTPUT

PCM-CONTROLLED GROUND

STARTER RELAY OUTPUT

87A

NO CONNECT

RELAY CIRCUIT TEST

(1) The relay common feed terminal cavity (30) is

connected to battery voltage and should be hot at all
times. If OK, go to Step 2. If 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. If OK,
go to Step 4. If not OK, repair the open circuit to the
starter solenoid as required.

(4) The coil battery terminal (85) is connected to

the electromagnet in the relay. It is energized when
the ignition switch is held in the Start position and
the clutch pedal is depressed (manual trans). Check
for battery voltage at the cavity for relay terminal 86
with the ignition switch in the Start position and the
clutch pedal is depressed (manual trans), and no
voltage when the ignition switch is released to the
On position. If OK, go to Step 5. If not OK, check for
an open or short circuit to the ignition switch and
repair, if required. If the circuit to the ignition switch
is OK, see the Ignition Switch Test procedure in this
group.

(5) The coil ground terminal (86) is connected to

the electromagnet in the relay. It is grounded by the
PCM if the conditions are right to start the car. For
automatic trans. cars the PCM must see Park Neu-
tral switch low and near zero engine speed (rpm).
For manual trans. cars the PCM only needs to see

near zero engine speed (rpm) and low clutch inter-
lock input and see near zero engine speed (rpm). To
diagnose the Park Neutral switch of the trans range
sensor refer to the transaxle section. Check for conti-
nuity to ground while the ignition switch is in the
start position and if equipped the clutch pedal
depressed. If not OK and the vehicle has an auto-
matic trans. verify Park Neutral switch operation. If
that checks OK check for continuity between PCM
and the terminal 86. Repair open circuit as required.
Also check the clutch interlock switch operation if
equipped with a manual transmission. If OK, the
PCM may be defective.

SAFETY SWITCHES

For diagnostics of the Transmission Range Sensor,

refer to the Transaxle section for more information.

If equipped with Clutch Interlock/Upstop Switch,

refer to Diagnosis and Testing in the Clutch section.

IGNITION SWITCH

After testing starter solenoid and relay, test igni-

tion switch and wiring. Refer to the Ignition Section
or Wiring Diagrams for more information. Check all
wiring for opens or shorts, and all connectors for
being loose or corroded.

BATTERY

For battery diagnosis and testing, refer to the Bat-

tery section for procedures.

ALL RELATED WIRING AND CONNECTORS

Refer to Wiring Diagrams for more information.

DIAGNOSIS AND TESTING - FEED CIRCUIT
RESISTANCE TEST

Before proceeding with this operation, review Diag-

nostic Preparation and Starter Feed Circuit Tests.
The following operation will require a voltmeter,
accurate to 1/10 of a volt.

CAUTION: Ignition and Fuel systems must be dis-
abled to prevent engine start while performing the
following tests.

(1) To disable the Ignition and Fuel systems, dis-

connect the Automatic Shutdown Relay (ASD). The
ASD relay is located in the Power Distribution Cen-
ter (PDC). Refer to the PDC cover for proper relay
location.

(2) Gain access to battery terminals.
(3) With all wiring harnesses and components

properly connected, perform the following:

(a) Connect the negative lead of the voltmeter to

the battery negative post, and positive lead to the
battery negative cable clamp. Rotate and hold the

Starter Relay Pinout

8F - 26

STARTING

STARTING (Continued)

ignition switch in the START position. Observe the
voltmeter. If voltage is detected, correct poor con-
tact between cable clamp and post.

(b) Connect positive lead of the voltmeter to the

battery positive post, and negative lead to the bat-
tery positive cable clamp. Rotate and hold the igni-
tion switch key in the START position. Observe the
voltmeter. If voltage is detected, correct poor con-
tact between the cable clamp and post.

negative terminal, and positive lead to engine
block near the battery cable attaching point.
Rotate and hold the ignition switch in the START
position. If voltage reads above 0.2 volt, correct
poor contact at ground cable attaching point. If
voltage reading is still above 0.2 volt after correct-
ing poor contacts, replace ground cable.
(4) Connect positive voltmeter lead to the starter

motor housing and the negative lead to the battery
negative terminal. Hold the ignition switch key in
the START position. If voltage reads above 0.2 volt,
correct poor starter to engine ground.

(a) Connect the positive voltmeter lead to the

battery positive terminal, and negative lead to bat-
tery cable terminal on starter solenoid. Rotate and
hold the ignition switch in the START position. If
voltage reads above 0.2 volt, correct poor contact at
battery cable to solenoid connection. If reading is

still above 0.2 volt after correcting poor contacts,
replace battery positive cable.

(b) If resistance tests do not detect feed circuit

failures, replace the starter motor.

SPECIFICATIONS

STARTER

MANUFACTURER

NIPPONDENSO

MELCO

ENGINE
APPLICATION

3.5L

2.7L

POWER RATING

1.4 KW

VOLTAGE

12 VOLTS

BRUSHES

DRIVE

OFFSET

PLANETARY

GEAR
REDUCED

GEAR TRAIN

CRANKING
AMPERAGE*

150 - 280 AMP*

DRAW TEST

NOTE: Engine should be up to operating tempera-
ture. Extremely heavy oil or tight engine will
increase starter amperage draw.

SPECIFICATIONS - TORQUE

DESCRIPTION

N·m

Ft. Lbs.

In. Lbs.

Starter Mounting Bolts

–

Starter Solenoid Battery Nut

–

STARTING

8F - 27

STARTING (Continued)

STARTER MOTOR

DESCRIPTION

DESCRIPTION - 2.7L

The Melco is a permanent magnet starter motor.

DESCRIPTION - 3.5L

The Nippondenso is a reduction gear-field coil

starter motor.

OPERATION

OPERATION - 2.7L

A planetary gear train transmits power between

starter motor and pinion shaft. The fields have per-
manent magnets.

OPERATION - 3.5L

Power is applied to the coil windings which causes

the pinion to rotate the ring gear mounted on the
drive plate.

REMOVAL

(1) Disconnect and isolate the battery negative

remote cable from remote ground post (Fig. 1).

(2) Raise vehicle.
(3) Remove three bolts attaching starter to engine

(Fig. 2).

(4) Remove battery positive feed wire from starter.
(5) Remove starter solenoid assembly from trans-

mission housing. Position the starter to gain access

to the Connector Positive Assurance (CPA) wiring
connector.

(6) Position jack stand beneath engine and slightly

lift to relieve pressure from left engine mount.

(7) Remove three left engine mount mounting bolts

from engine block.

(8) Jack engine up slightly to give more room to

maneuver starter assembly.

(9) Slide rear of starter motor out between catalyst

and engine mount.

(10) Disconnect posi-lock starter solenoid connec-

tor.

(11) Remove the starter from vehicle.

INSTALLATION

(1) Connect battery positive feed wire to starter.
(2) Connect posi-lock starter solenoid connector.
(3) Jack engine up slightly to give more room to

maneuver starter assembly.

(4) Install the starter.
(5) Install three bolts attaching starter to engine

(Fig. 2). Tighten all fasteners to the proper torque.
Refer to the Torque Specifications chart in this section.

(6) Install three left engine mount mounting bolts

to engine block.

(7) Install starter solenoid assembly from trans-

mission housing. Position the starter to gain access
to the Connector Positive Assurance (CPA) wiring
connector.

(8) Lower vehicle.
(9) Connect the battery negative cable (Fig. 1).

Fig. 1 NEGATIVE BATTERY CABLE

1 - RIGHT STRUT TOWER
2 - AIR CLEANER INLET TUBE
3 - REMOTE TERMINAL

Fig. 2 STARTER 3.5L

1 - STARTER SHIELD RETENTION SLEEVE
2 - COVER
3 - TRANSAXLE HOUSING (3)
4 - GROUND CABLE

8F - 28

STARTING

Content .. 70 71 72 73 ..