Chrysler 300M, Dodge Interpid. Manual - part 66

stalled equipment on this model. All of the compo-
nents of the battery system are located in the front of
the vehicle, just in front of the right front wheel and
tire assembly. The battery system for this vehicle
covers the following related components, which are

covered in further detail later in this section of the
service manual:

• Battery - The storage battery provides a reli-

able means of storing a renewable source of electrical
energy within the vehicle.

• Battery Cables - The battery cables connect

the positive and negatively charged battery terminal
posts to the vehicle electrical system.

• Battery Holddown - The battery holddown

hardware secures the battery in the battery tray in
the engine compartment.

ENGINE SYSTEMS

8F - 1

• Battery Heater Blanket - The battery heater

blanket is used to improve battery cold start ability.

• Battery Tray - The battery tray provides a

secure mounting location in the vehicle for the bat-
tery and an anchor point for the battery holddown
hardware.

For battery system maintenance schedules and/or

jump starting procedure, refer to the Lubrication and
Maintenance section of this manual or the owners
manual. The battery must be fully-charged before
any battery system diagnosis or testing procedures
can be performed.

OPERATION

The battery system is designed to provide a safe,

efficient, reliable and mobile means of delivering and
storing electrical energy. This electrical energy is
required to operate the engine starting system, as
well as to operate many of the other vehicle acces-
sory systems for limited durations while the engine
and/or the charging system are not operating. The
battery system is also designed to provide a reserve
of electrical energy to supplement the charging sys-
tem for short durations while the engine is running
and the electrical current demands of the vehicle
exceed the output of the charging system. In addition
to delivering, and storing electrical energy for the
vehicle, the battery system serves as a capacitor and
voltage stabilizer for the vehicle electrical system. It
absorbs most abnormal or transient voltages caused
by the switching of any of the electrical components
or circuits in the vehicle.

DIAGNOSIS AND TESTING - BATTERY SYSTEM

The battery, starting, and charging systems in the

vehicle operate with one another and must be tested
as a complete system. In order for the engine to start
and the battery to maintain its charge properly, all of

the components that are used in these systems must
perform within specifications. It is important that
the battery, starting, and charging systems be thor-
oughly tested and inspected any time a battery needs
to be charged or replaced. The cause of abnormal bat-
tery discharge, overcharging or early battery failure
must be diagnosed and corrected before a battery is
replaced and before a vehicle is returned to service.
The service information for these systems has been
separated within this service manual to make it eas-
ier to locate the specific information you are seeking.
However, when attempting to diagnose any of these
systems, it is important that you keep their interde-
pendency in mind.

The diagnostic procedures used for the battery,

starting, and charging systems include the most
basic conventional diagnostic methods, to the more
sophisticated On-Board Diagnostics (OBD) built into
the Powertrain Control Module (PCM). Use of an
induction-type milliampere ammeter, a volt/ohmme-
ter, a battery charger, a carbon pile rheostat (load
tester) and a 12-volt test lamp may be required. All
OBD-sensed systems are monitored by the PCM.
Each monitored circuit is assigned a Diagnostic Trou-
ble Code (DTC). The PCM will store a DTC in elec-
tronic memory for any failure it detects. Refer to
Charging System for the proper charging system on-
board diagnostic test procedures.

MICRO 420 BATTERY TESTER

The Micro 420 automotive battery system tester is

designed to help the dealership technicians diagnose
the cause of a defective battery. Follow the instruc-
tion manual supplied with the tester to properly
diagnose a vehicle. If the instruction manual is not
available refer to the standard procedure in this sec-
tion, which includes the directions for using the
Micro 420 battery tester.

8F - 2

BATTERY SYSTEM

BATTERY SYSTEM (Continued)

BATTERY SYSTEM DIAGNOSIS

CONDITION

POSSIBLE CAUSES

CORRECTION

THE BATTERY SEEMS
WEAK OR DEAD WHEN
ATTEMPTING TO START
THE ENGINE.

1. The electrical system
ignition-off draw is excessive.

1. Refer to the IGNITION-OFF DRAW TEST
Standard Procedure for the proper test
procedures. Repair the excessive ignition-off
draw, as required.

2. The charging system is
faulty.

2. Determine if the charging system is performing
to specifications. Refer to Charging System for
additional charging system diagnosis and testing
procedures. Repair the faulty charging system, as
required.

3. The battery is discharged.

3. Determine the battery state-of-charge using the
Micro 420 battery tester. Refer to the Standard
Procedures in this section for additional test
procedures. Charge the faulty battery, as
required.

4. The battery terminal
connections are loose or
corroded.

4. Refer to Battery Cables for the proper battery
cable diagnosis and testing procedures. Clean
and tighten the battery terminal connections, as
required.

5. The battery has an
incorrect size or rating for
this vehicle.

5. Refer to Battery System Specifications for the
proper size and rating. Replace an incorrect
battery, as required.

6. The battery is faulty.

6. Determine the battery cranking capacity using
the Micro 420 battery tester. Refer to the
Standard Procedures in this section for additional
test procedures. Replace the faulty battery, as
required.

7. The starting system is
faulty.

7. Determine if the starting system is performing
to specifications. Refer to Starting System for the
proper starting system diagnosis and testing
procedures. Repair the faulty starting system, as
required.

8. The battery is physically
damaged.

8. Inspect the battery for loose terminal posts or a
cracked and leaking case. Replace the damaged
battery, as required.

BATTERY SYSTEM

8F - 3

BATTERY SYSTEM (Continued)

BATTERY SYSTEM DIAGNOSIS

CONDITION

POSSIBLE CAUSES

CORRECTION

THE BATTERY STATE OF
CHARGE CANNOT BE
MAINTAINED.

1. The battery has an
incorrect size or rating for
this vehicle.

1. Refer to Battery System Specifications for the
proper specifications. Replace an incorrect
battery, as required.

2. The battery terminal
connections are loose or
corroded.

2. Refer to Battery Cable for the proper cable
diagnosis and testing procedures. Clean and
tighten the battery terminal connections, as
required.

3. The electrical system
ignition-off draw is excessive.

3. Refer to the IGNITION-OFF DRAW TEST
Standard Procedure for the proper test
procedures. Repair the faulty electrical system, as
required.

4. The battery is faulty.

4. Test the battery using the Micro 420 battery
tester. Refer to Standard Procedures for
additional test procedures. Replace the faulty
battery, as required.

5. The starting system is
faulty.

5. Determine if the starting system is performing
to specifications. Refer to Starting System for the
proper starting system diagnosis and testing
procedures. Repair the faulty starting system, as
required.

6. The charging system is
faulty.

6. Determine if the charging system is performing
to specifications. Refer to Charging System for
additional charging system diagnosis and testing
procedures. Repair the faulty charging system, as
required.

7. Electrical loads exceed the
output of the charging
system.

7. Inspect the vehicle for aftermarket electrical
equipment which might cause excessive electrical
loads.

8. Slow driving or prolonged
idling with high-amperage
draw systems in use.

8. Advise the vehicle operator, as required.

THE BATTERY WILL NOT
ACCEPT A CHARGE.

1. The battery is faulty.

1. Test the battery using the Micro 420 battery
tester.. Charge or replace the faulty battery, as
required.

ABNORMAL BATTERY DISCHARGING

Any of the following conditions can result in abnor-

mal battery discharging:

1. A faulty or incorrect charging system compo-

nent. Refer to Charging System for charging system
diagnosis and testing procedures.

2. A faulty or incorrect battery. Use Micro 420

tester and refer to Battery System for additional bat-
tery diagnosis and testing procedures.

3. A faulty circuit or component causing excessive

ignition-off draw.

4. Electrical loads that exceed the output of the

charging system. This can be due to equipment

installed after manufacture, or repeated short trip
use.

5. A faulty or incorrect starting system component.

Refer to Starting System for the proper starting sys-
tem diagnosis and testing procedures.

6. Corroded or loose battery posts and/or terminal

clamps.

7. Slow driving speeds (heavy traffic conditions) or

prolonged idling, with high-amperage draw systems
in use.

CLEANING

The following information details the recommended

cleaning procedures for the battery and related com-

8F - 4

BATTERY SYSTEM

BATTERY SYSTEM (Continued)

Content .. 64 65 66 67 ..