Jeep 1997 Grand Cherokee Service Manual page 301

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GENERAL INFORMATION
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . 1
OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
DESCRIPTION AND OPERATION
BATTERY MOUNTING . . . . . . . . . . . . . . . . . . . . 3
BATTERY SIZE AND RATINGS . . . . . . . . . . . . . . 2
BATTERY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
DIAGNOSIS AND TESTING
BATTERY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
BUILT-IN TEST INDICATOR . . . . . . . . . . . . . . . . 6
HYDROMETER TEST . . . . . . . . . . . . . . . . . . . . . 6
GENERAL INFORMATION
OVERVIEW
The battery, starting, and charging systems oper-
ate with one another, and must be tested as a com-
plete system. In order for the vehicle to start and
charge properly, all of the components involved in
these systems must perform within specifications.
Group 8A covers the battery, Group 8B covers the
starting system, and Group 8C covers the charging
system. Refer to Group 8W - Wiring Diagrams for
complete circuit descriptions and diagrams. We have
separated these systems to make it easier to locate
the information you are seeking within this Service
Manual. However, when attempting to diagnose any
of these systems, it is important that you keep their
interdependency in mind.
The diagnostic procedures used in these groups
include the most basic conventional diagnostic meth-
ods, to the more sophisticated On-Board Diagnostics
(OBD) built into the Powertrain Control Module
(PCM). Use of a induction milliampere ammeter, volt/
ohmmeter, battery charger, carbon pile rheostat (load
tester), and 12-volt test lamp may be required.
All OBD-sensed systems are monitored by the
PCM. Each monitored circuit is assigned a Diagnos-
tic Trouble Code (DTC). The PCM will store a DTC in
electronic memory for any failure it detects. See the
On-Board Diagnostics Test in Group 8C - Charging
System for more information.
INTRODUCTION
This section covers only battery diagnostic and ser-
vice procedures. For battery maintenance procedures,
refer to Group 0 - Lubrication and Maintenance.
While battery charging can be considered a mainte-
POSITIVE NANCE LOW-MAINTE- POST TERY BAT-
BATTERY
CONTENTS
page
IGNITION-OFF DRAW TEST . . . . . . . . . . . . . . . 10
LOAD TEST . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
OPEN-CIRCUIT VOLTAGE TEST . . . . . . . . . . . . 8
VOLTAGE DROP TEST . . . . . . . . . . . . . . . . . . . 11
SERVICE PROCEDURES
BATTERY CHARGING . . . . . . . . . . . . . . . . . . . 12
REMOVAL AND INSTALLATION
BATTERY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
SPECIFICATIONS
BATTERY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
nance procedure, battery charging information is
located in this group. This was done because the bat-
tery must be fully-charged before any diagnosis can
be performed.
The factory-installed low-maintenance battery has
removable battery cell caps. Water can be added to
this battery. The battery is not sealed and has vent
holes in the cell caps (Fig. 1). The chemical composi-
tion within the low-maintenance battery reduces bat-
tery gassing and water loss, at normal charge and
discharge rates.
Fig. 1 Low-Maintenance Battery - Typical
Rapid loss of electrolyte can be caused by an over-
charging condition. Be certain to diagnose the charg-
ing system before returning the vehicle to service.
Refer to Group 8C - Charging System for more infor-
mation.
The factory-installed battery in a North American-
built vehicle also has a built-in test indicator
(hydrometer). The color visible in the sight glass of
PLATE GROUPS VENT TEST ELECTROLYTE INDICA- TOR LEVEL
BATTERY
VENT GREEN BALL NEGATIVE POST
8A - 1
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