Module CHRYSLER VOYAGER 2005 Workshop Manual

INSTALLATION
(1) Install the Power Liftgate (PLG) control mod-
ule on the D-pillar and install retaining screw.
(2) Connect the wire harness connections to the
PLG control module. Be certain to slide connector
locks to the locked position.
(3) Install the D-pillar trim panel on the vehicle.
(Refer to 23 - BODY/INTERIOR/LEFT D-PILLAR
TRIM PANEL - INSTALLATION)
(4) Connect the battery negative cable.
(5) Using an appropriate scan tool, check and
erase any PLG control module diagnostic trouble
codes.
(6) Verify PLG system operation. Cycle the PLG
through one complete open and close cycle, this will
allow the PLG control module to relearn its cycle
with the new components.
POWERTRAIN CONTROL
MODULE
DESCRIPTION
DESCRIPTION
The Powertrain Control Module (PCM) is a digital
computer containing a microprocessor (Fig. 9). ThePCM receives input signals from various switches
and sensors referred to as Powertrain Control Mod-
ule Inputs. Based on these inputs, the PCM adjusts
various engine and vehicle operations through
devices referred to as Powertrain Control Module
Outputs.
NOTE: PCM Inputs:
²Air Conditioning Pressure Transducer
²Ambient temperature Sensor
²ASD Relay
²Battery Temperature Sensor (NGC)
²Battery Voltage
²Brake Switch
²Camshaft Position Sensor
²Crankshaft Position Sensor
²Distance Sensor (from transmission control mod-
ule)
²EGR Position Feedback
²Engine Coolant Temperature Sensor
²Heated Oxygen Sensors
²Ignition sense
²Intake Air Temperature Sensor
²Knock Sensor
²Leak Detection Pump Feedback
²Manifold Absolute Pressure (MAP) Sensor
²Park/Neutral
²PCI Bus
²Power Steering Pressure Switch
²Proportional Purge Sense
Fig. 8 POWER LIFTGATE CONTROL MODULE
1 - POWER LIFTGATE CONTROL MODULE
2 - RETAINING SCREWS
3 - D-PILLAR
4 - POWER LIFTGATE MOTOR
5 - ELECTRICAL CONNECTORS
Fig. 9 Powertrain Control Module (PCM)
1 - Battery
2 - Power Distribution Center
3 - Powertrain Control Module
RSELECTRONIC CONTROL MODULES8E-11
POWER LIFTGATE CONTROL MODULE (Continued)

²SCI Receive
²Speed Control
²Throttle Position Sensor
²Transmission Control Relay (Switched B+)
²Transmission Pressure Switches
²Transmission Temperature Sensor
²Transmission Input Shaft Speed Sensor
²Transmission Output Shaft Speed Sensor
²Transaxle Gear Engagement
²Vehicle Speed
NOTE: PCM Outputs:
²Air Conditioning Clutch Relay
²Automatic Shut Down (ASD) and Fuel Pump
Relays
²Data Link Connector (PCI and SCI Transmit)
²Double Start Override
²EGR Solenoid
²Fuel Injectors
²Generator Field
²High Speed Fan Relay
²Idle Air Control Motor
²Ignition Coils
²Leak Detection Pump
²Low Speed Fan Relay
²MTV Actuator
²Proportional Purge Solenoid
²SRV Valve
²Speed Control Relay
²Speed Control Vent Relay
²Speed Control Vacuum Relay
²8 Volt Output
²5 Volt Output
²Torque Reduction Request
²Transmission Control Relay
²Transmission Solenoids
²Vehicle Speed
Based on inputs it receives, the powertrain control
module (PCM) adjusts fuel injector pulse width, idle
speed, ignition timing, and canister purge operation.
The PCM regulates the cooling fans, air conditioning
and speed control systems. The PCM changes gener-
ator charge rate by adjusting the generator field.
The PCM adjusts injector pulse width (air-fuel
ratio) based on the following inputs.
²Battery Voltage
²Intake Air Temperature Sensor
²Engine Coolant Temperature
²Engine Speed (crankshaft position sensor)
²Exhaust Gas Oxygen Content (heated oxygen
sensors)
²Manifold Absolute Pressure
²Throttle Position
The PCM adjusts engine idle speed through the
idle air control motor based on the following inputs.
²Brake Switch²Engine Coolant Temperature
²Engine Speed (crankshaft position sensor)
²Park/Neutral
²Transaxle Gear Engagement
²Throttle Position
²Vehicle Speed
The PCM adjusts ignition timing based on the fol-
lowing inputs.
²Intake Air Temperature
²Engine Coolant Temperature
²Engine Speed (crankshaft position sensor)
²Knock Sensor
²Manifold Absolute Pressure
²Park/Neutral
²Transaxle Gear Engagement
²Throttle Position
The automatic shut down (ASD) and fuel pump
relays are mounted externally, but turned on and off
by the powertrain control module through the same
circuit.
The camshaft and crankshaft signals are sent to
the powertrain control module. If the PCM does not
receive both signals within approximately one second
of engine cranking, it deactivates the ASD and fuel
pump relays. When these relays are deactivated,
power is shut off to the fuel injectors, ignition coils,
fuel pump and the heating element in each oxygen
sensor.
The PCM contains a voltage converter that
changes battery voltage to a regulated 8.0 volts. The
8.0 volts power the camshaft position sensor, crank-
shaft position sensor and vehicle speed sensor. The
PCM also provides a 5.0 volts supply for the engine
coolant temperature sensor, intake air temperature
sensor, manifold absolute pressure sensor and throt-
tle position sensor.
The PCM engine control strategy prevents reduced
idle speeds until after the engine operates for 320 km
(200 miles). If the PCM is replaced after 320 km (200
miles) of usage, update the mileage in new PCM. Use
the DRBIIItscan tool to change the mileage in the
PCM. Refer to the appropriate Powertrain Diagnostic
Manual and the DRBIIItscan tool.
TRANSMISSION CONTROL
CLUTCH VOLUME INDEX (CVI)
An important function of the PCM is to monitor
Clutch Volume Index (CVI). CVIs represent the vol-
ume of fluid needed to compress a clutch pack.
The PCM monitors gear ratio changes by monitor-
ing the Input and Output Speed Sensors. The Input,
or Turbine Speed Sensor sends an electrical signal to
the PCM that represents input shaft rpm. The Out-
put Speed Sensor provides the PCM with output
shaft speed information.
8E - 12 ELECTRONIC CONTROL MODULESRS
POWERTRAIN CONTROL MODULE (Continued)

By comparing the two inputs, the PCM can deter-
mine transaxle gear ratio. This is important to the
CVI calculation because the PCM determines CVIs
by monitoring how long it takes for a gear change to
occur (Fig. 10).
Gear ratios can be determined by using the DRB
Scan Tool and reading the Input/Output Speed Sen-
sor values in the ªMonitorsº display. Gear ratio can
be obtained by dividing the Input Speed Sensor value
by the Output Speed Sensor value.
For example, if the input shaft is rotating at 1000
rpm and the output shaft is rotating at 500 rpm,
then the PCM can determine that the gear ratio is
2:1. In direct drive (3rd gear), the gear ratio changes
to 1:1. The gear ratio changes as clutches are applied
and released. By monitoring the length of time it
takes for the gear ratio to change following a shift
request, the PCM can determine the volume of fluid
used to apply or release a friction element.
The volume of transmission fluid needed to apply
the friction elements are continuously updated for
adaptive controls. As friction material wears, the vol-
ume of fluid need to apply the element increases.
Certain mechanical problems within the clutch
assemblies (broken return springs, out of position
snap rings, excessive clutch pack clearance, improper
assembly, etc.) can cause inadequate or out-of-range
clutch volumes. Also, defective Input/Output Speed
Sensors and wiring can cause these conditions. The
following chart identifies the appropriate clutch vol-
umes and when they are monitored/updated:
CLUTCH VOLUMES
ClutchWhen Updated
Proper Clutch
Volume
Shift Sequence Oil Temperature Throttle Angle
L/R2-1 or 3-1 coast
downshift>70É <5É 35to83
2/4 1-2 shift
> 110É5 - 54É20 to 77
OD 2-3 shift 48 to 150
UD 4-3 or 4-2 shift > 5É 24 to 70
SHIFT SCHEDULES
As mentioned earlier, the PCM has programming
that allows it to select a variety of shift schedules.
Shift schedule selection is dependent on the follow-
ing:
²Shift lever position
²Throttle position²Engine load
²Fluid temperature
²Software level
As driving conditions change, the PCM appropri-
ately adjusts the shift schedule. Refer to the follow-
ing chart to determine the appropriate operation
expected, depending on driving conditions.
Fig. 10 Example of CVI Calculation
1 - OUTPUT SPEED SENSOR
2 - OUTPUT SHAFT
3 - CLUTCH PACK
4 - SEPARATOR PLATE
5 - FRICTION DISCS
6 - INPUT SHAFT
7 - INPUT SPEED SENSOR
8 - PISTON AND SEAL
RSELECTRONIC CONTROL MODULES8E-13
POWERTRAIN CONTROL MODULE (Continued)

Schedule Condition Expected Operation
Extreme ColdOil temperature at start-up below
-16É FPark, Reverse, Neutral and 2nd
gear only (prevents shifting which
may fail a clutch with frequent
shifts)
ColdOil temperature at start-up above
-12É F and below 36É F± Delayed 2-3 upshift
(approximately 22-31 mph)
± Delayed 3-4 upshift (45-53 mph)
± Early 4-3 costdown shift
(approximately 30 mph)
± Early 3-2 coastdown shift
(approximately 17 mph)
± High speed 4-2, 3-2, 2-1 kickdown
shifts are prevented
± No EMCC
WarmOil temperature at start-up above
36É F and below 80 degree F± Normal operation (upshift,
kickdowns, and coastdowns)
± No EMCC
HotOil temperature at start-up above
80É F± Normal operation (upshift,
kickdowns, and coastdowns)
± Full EMCC, no PEMCC except to
engage FEMCC (except at closed
throttle at speeds above 70-83 mph)
OverheatOil temperature above 240É F or
engine coolant temperature above
244É F± Delayed 2-3 upshift (25-32 mph)
± Delayed 3-4 upshift (41-48 mph)
± 3rd gear FEMCC from 30-48 mph
± 3rd gear PEMCC from 27-31 mph
Super OverheatOil temperature above 260É F ± All9Overheat9shift schedule
features apply
± 2nd gear PEMCC above 22 mph
± Above 22 mph the torque
converter will not unlock unless the
throttle is closed or if a wide open
throttle 2nd PEMCC to 1 kickdown
is made
OPERATION - SENSOR RETURN - PCM INPUT
The sensor return circuit provides a low electrical
noise ground reference for all of the systems sensors.
The sensor return circuit connects to internal ground
circuits within the Powertrain Control Module
(PCM).
OPERATION - DATA BUS COMMUNICATION
RECEIVE - PCM INPUT
The PCM uses the SCI communication bus to pre-
form engine diagnostics and flash operations. The
transmission side of the PCM uses the SCI commu-
nication bus to flash new software. However, diagnos-tics is performed via the vehicles J1850 bus for the
transmission side of the PCM.
OPERATION - IGNITION SENSE - PCM INPUT
The ignition sense input informs the Powertrain
Control Module (PCM) that the ignition switch is in
the crank or run position.
OPERATION - PCM GROUND
Ground is provided through multiple pins of the
PCM connector. Depending on the vehicle there may
be as many as two different ground pins. There are
power grounds and sensor grounds.
8E - 14 ELECTRONIC CONTROL MODULESRS
POWERTRAIN CONTROL MODULE (Continued)

The power grounds are used to control the ground
side relays, solenoids, ignition coil or injectors. The
signal ground is used for any input that uses sensor
return for ground, and the ground side of any inter-
nal processing component.
The PCM case is shielded to prevent RFI and EMI.
The PCM case is grounded and must be firmly
attached to a good, clean body ground.
Internally all grounds are connected together, how-
ever there is noise suppression on the sensor ground.
For EMI and RFI protection the housing and cover
are also grounded separately from the ground pins.
OPERATION - 5 VOLT SUPPLY - PCM OUTPUT
The PCM supplies 5 volts to the following sensors:
²A/C pressure transducer
²Ambient Temperature sensor
²Battery temperature
²Camshaft Position Sensor (NGC)
²Crankshaft Position Sensor (NGC)
²Engine coolant temperature sensor
²Inlet Air Temperature Sensor
²Knock sensor
²Linear EGR solenoid (if equipped)
²Manifold absolute pressure sensor
²Oil Pressure Switch
²Throttle position sensor
STANDARD PROCEDURE
STANDARD PROCEDURE - OBTAINING
DIAGNOSTIC TROUBLE CODES
BULB CHECK
Key on: Bulb illuminated until vehicle starts, as
long as all once per trip (readiness) monitors com-
pleted. If monitors havenotbeen completed, then:
Key on: bulb check for about 5 to 8 seconds, lamp
then flashes if once per trip (readiness) monitors
havenotbeen completed until vehicle is started,
then MIL is extinguished.
OBTAINING DTC'S USING DRB SCAN TOOL
(1) Connect the DRB scan tool to the data link
(diagnostic) connector. This connector is located in
the passenger compartment; at the lower edge of
instrument panel; near the steering column.
(2) Turn the ignition switch on and access the
ªRead Faultº screen.
(3) Record all the DTC's and ªfreeze frameº infor-
mation shown on the DRB scan tool.
(4) To erase DTC's, use the ªErase Trouble Codeº
data screen on the DRB scan tool.Do not erase any
DTC's until problems have been investigated
and repairs have been performed.
STANDARD PROCEDURE - PINION FACTOR
SETTING
NOTE: This procedure must be performed if the
PCM has been replaced with a NEW or replacement
unit. Failure to perform this procedure will result in
an inoperative or improperly calibrated speedome-
ter.
The vehicle speed readings for the speedometer are
taken from the output speed sensor. The PCM must
be calibrated to the different combinations of equip-
ment (final drive and tires) available. Pinion Factor
allows the technician to set the Powertrain Control
Module initial setting so that the speedometer read-
ings will be correct. To properly read and/or reset the
Pinion Factor, it is necessary to use a DRBIIItscan
tool.
(1) Plug the DRBIIItscan tool into the diagnostic
connector located under the instrument panel.
(2) Select the Transmission menu.
(3) Select the Miscellaneous menu.
(4) Select Pinion Factor. Then follow the instruc-
tions on the DRBIIItscan tool screen.
STANDARD PROCEDURE - QUICK LEARN
PROCEDURE
The quick learn procedure requires the use of the
DRBIIItscan tool. This program allows the PCM to
recalibrate itself. This will provide the best possible
transaxle operation.
NOTE: The quick learn procedure should be per-
formed if any of the following procedures are per-
formed:
²Transaxle Assembly Replacement
²Powertrain Control Module Replacement
²Solenoid/Pressure Switch Assembly Replacement
²Clutch Plate and/or Seal Replacement
²Valve Body Replacement or Recondition
To perform the Quick Learn Procedure, the follow-
ing conditions must be met:
²The brakes must be applied
²The engine speed must be above 500 rpm
²The throttle angle (TPS) must be less than 3
degrees
²The shift lever position must stay until
prompted to shift to overdrive
²The shift lever position must stay in overdrive
after the Shift to Overdrive prompt until the
DRBIIItindicates the procedure is complete
²The calculated oil temperature must be above
60É and below 200É
RSELECTRONIC CONTROL MODULES8E-15
POWERTRAIN CONTROL MODULE (Continued)

(1) Plug the DRBIIItscan tool into the diagnostic
connector. The connector is located under the instru-
ment panel.
(2) Go to the Transmission screen.
(3) Go to the Miscellaneous screen.
(4) Select Quick Learn Procedure. Follow the
instructions of the DRBIIItto perform the Quick
Learn Procedure.
REMOVAL
REMOVAL - SBEC CONTROLLER
(1) Disconnect the negative battery cable.
(2) Remove the battery shield, refer to the Battery
section for more information.
(3) Remove the 2 upper PCM bracket bolts (Fig.
11).
(4) Remove the 2 PCM connectors.
(5) Remove the headlamp, refer to the Lamps sec-
tion for more information.
(6) Remove the lower PCM mounting bolt (Fig. 12).
(7) Remove PCM.
REMOVAL - NGC CONTROLLER
The PCM engine control strategy prevents reduced
idle speeds until after the engine operates for 320 km
(200 miles). If the PCM is replaced after 320 km (200
miles) of usage, update the mileage and vehicle iden-
tification number (VIN) in the new PCM. Use the
DRBIIItscan tool to change the millage and VIN in
the PCM. If this step is not done a Diagnostic Trou-
ble Code (DTC) may be set. Refer to the appropriate
Powertrain Diagnostic Manual and the DRBIIItscan
tool.
Fig. 11 PCM
1 - Attaching Bolts
Fig. 12 PCM LOWER BOLT
NGC CONTROLLER LOCATION
8E - 16 ELECTRONIC CONTROL MODULESRS
POWERTRAIN CONTROL MODULE (Continued)

(1) Turn wheels to the left.
(2) Disconnect the negative battery cable.
(3) Raise vehicle and support.
(4) Remove the left front wheel well splash shield
(Fig. 13).
(5) Unlock and disconnect the electrical connectors
(Fig. 14).
(6) Remove 3 screws from PCM to mounting
bracket.
(7) Remove the PCM.INSTALLATION
INSTALLATION - SBEC CONTROLLER
(1) Install the PCM.
(2) Install the lower PCM mounting bolt. Tighten
bolt.
(3) Install the 2 upper PCM bracket bolts. Tighten
bolt.
(4) Install the headlamp, refer to the Lamps sec-
tion for more information.
(5) Install the 2 PCM connectors.
(6) Install the battery shield, refer to the Battery
section for more information.
(7) Connect the negative battery cable.
INSTALLATION
The PCM engine control strategy prevents reduced
idle speeds until after the engine operates for 320 km
(200 miles). If the PCM is replaced after 320 km (200
miles) of usage, update the mileage and vehicle iden-
tification number (VIN) in the new PCM. Use the
DRBIIItscan tool to change the millage and VIN in
the PCM. If this step is not done a diagnostic trouble
code (DTC) may be set and SKIM must be done or
car will not start if it is a SKIM equipped car. If a
SKIM car you must do a secret key transfer also.
Refer to the appropriate Powertrain Diagnostic Man-
ual and the DRBIIItscan tool.
(1) Install PCM module to the mounting bracket.
(2) Install electrical connectors and lock.
(3) Install the splash shield.
(4) Lower vehicle.
(5) Connect the negative battery cable.
(6) Using DRBIIItscan tool, program mileage and
vehicle identification number (VIN) into PCM. Refer
to the DRBIIItscan tool and the appropriate Power-
train Diagnostic Manual.
Fig. 13 SPLASH SHIELD
Fig. 14 NGC CONTROLLER
RSELECTRONIC CONTROL MODULES8E-17
POWERTRAIN CONTROL MODULE (Continued)

SLIDING DOOR CONTROL
MODULE
DESCRIPTION
Vehicles equipped with a power sliding door system
utilize a sliding door control module. The sliding door
control module is located behind the sliding door trim
panel in the center of the door, just above the sliding
door motor (Fig. 15). This module controls the opera-
tion of the door through the Programmable Commu-
nication Interface (PCI) data bus circuit and the
Body Control Module (BCM). The sliding door control
module contains software technology which enables it
to detect resistance to door travel and to reverse door
travel in order to avoid damage to the door or to
avoid possible personal injury if the obstruction is a
person. This feature functions in both the opening
and closing cycles. If the power sliding door system
develops any problems the control module will store
and recall Diagnostic Trouble Codes (DTC). The use
of a diagnostic scan tool, such as the DRB IIItis
required to read and troubleshoot these trouble
codes. The sliding door control module can be
reflashed if necessary. Refer to the latest Technical
Service Bulletin (TSB) Information for any updates.The power door control module is a replaceable
component and cannot be repaired, if found to be
faulty it must be replaced.
OPERATION
The power sliding door control module serves as
the main computer for the power sliding door system.
All power door functions are processed through the
power sliding door control module and/or the vehicles
Body Control Module (BCM). At the start of a power
open command, a signal is sent to the BCM and then
to the power sliding door control module via the Pro-
grammable Communication Interface (PCI) data bus
circuit. This signal, generated by any of the power
door command switches, tells the power sliding door
control module to activate a power latch release,
engage the clutch assembly and drive the door into
the full open position. If an obstacle is felt during
this power open cycle, the module will reverse direc-
tion and close the door. This process is also enabled
during a power close cycle. This process will repeat
three times, and if a fourth obstacle is detected, the
door will go into full manual mode. Once the full
open position is obtained, a hold open latch assembly
mounted full open switch tells the power sliding door
control module that the door has reached the full
open position. If the power sliding door system devel-
ops any problems the power sliding door control mod-
ule will store and recall Diagnostic Trouble Codes
(DTC). The use of a diagnostic scan tool, such as the
DRB IIItis required to read and troubleshoot these
trouble codes.
DIAGNOSIS AND TESTING
SLIDING DOOR CONTROL MODULE
Any diagnosis of the power sliding door sys-
tem should begin with the use of the DRB IIIt
diagnostic tool. For information on the use of
the DRB IIIt, refer to the appropriate Diagnos-
tic Procedures information.
Inspect the related wiring harness connectors for
broken, bent, pushed out, or corroded terminals.
Refer to the appropriate wiring information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the appropriate door trim panel from
the vehicle. (Refer to 23 - BODY/DOORS - SLIDING/
TRIM PANEL - REMOVAL)
(3) Remove the weather shield.
Fig. 15 Power Side Door Components
1 - SLIDING DOOR CONTROL MODULE
2 - MODULE RETAINING SCREW
3 - MODULE ELECTRICAL CONNECTORS
4 - DOOR MOTOR ASSEMBLY
5 - FLEX DRIVE ASSEMBLY
6 - DOOR MOTOR RETAINING FASTENERS
7 - DOOR MOTOR ELECTRICAL CONNECTOR
8E - 18 ELECTRONIC CONTROL MODULESRS

(4) Disconnect the power door control module elec-
trical connectors. Slide the red locking tab out (away
from module) and depress connector retaining tab,
while pulling straight apart.
(5) Remove the control module retaining screw
(Fig. 16).
(6) Remove the module from the vehicle.
INSTALLATION
(1) Position the sliding door control module and
install the retaining screw.
(2) Connect the electrical connectors. Slide the
locking tab into the locked position.
(3) Install the weather shield.
(4) Install the appropriate door trim panel on the
vehicle. (Refer to 23 - BODY/DOORS - SLIDING/
TRIM PANEL - INSTALLATION)
(5) Connect the battery negative cable.
(6) Using an appropriate scan tool, check and
erase any power door control module diagnostic trou-
ble codes.
(7) Verify power door system operation. Cycle the
power door through one complete open and close
cycle.
Fig. 16 Power Side Door Components
1 - SLIDING DOOR CONTROL MODULE
2 - MODULE RETAINING SCREW
3 - MODULE ELECTRICAL CONNECTORS
4 - DOOR MOTOR ASSEMBLY
5 - FLEX DRIVE ASSEMBLY
6 - DOOR MOTOR RETAINING FASTENERS
7 - DOOR MOTOR ELECTRICAL CONNECTOR
RSELECTRONIC CONTROL MODULES8E-19
SLIDING DOOR CONTROL MODULE (Continued)

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 failuremust 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 8 -
ELECTRICAL/CHARGING - DIAGNOSIS AND
TESTING) for the proper charging system on-board
diagnostic test procedures.MICRO 420 BATTERY TESTER
The Micro 420 automotive battery 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 SYSTEMRS
BATTERY SYSTEM (Continued)