alternator ISUZU TROOPER 1998 Service Repair Manual

6E±20
ENGINE DRIVEABILITY AND EMISSIONS
PCM Pinout Table, 32-Way White Connector ± Row ªCº (For EC)
TS23345
PINPIN FunctionWire ColorIGN ONENG RUNRefer To
C1Injector Cylinder #4GRN/REDB+B+General Description and
Operation, Fuel Injector
C2Shift ªBº SolenoidBRN/BLK0.0 V0.0 VAutomatic Transmission
(4L30E)
C3Injector Cylinder #6GRN/YELB+B+General Description and
Operation, Fuel Injector
C4Ignition Control (IC)
Cylinder #1RED0.0 V0.1 VGeneral Description and
Operation, Fuel Injector
C5Crankshaft Position
Sensor, ªAº CircuitYEL0.3 V to 5 V2.2 VGeneral Description and
Operation, Crankshaft
Position Sensor
C6Not UsedÐÐÐÐ
C7PCM GroundYEL0.0 V0.0 VChassis Electrical
C8PCM GroundBLK/PNK0.0 V0.0 VChassis Electrical
C9PCM GroundBLK/BLU0.0 V0.0 VChassis Electrical
C10TachometerBLK/RED8.8 V10.0 V
(at idle)Chassis Electrical
C11Variable Intake ManifoldYEL/BLK0.0 VB+ (rpm
3600 over)Manual Transmission
C12Alternator Control GainWHT/BLU10.5 VB+Chassis Electrical
C13Fuel PWMBLU/PNKB+B+Ð
C14Bank 2 HO2S 1 HighPNK0.4 V0.1-0.9 VGeneral Description and
Operation, Fuel HO2S 1
C15Bank 2 HO2S 1 LowBLU0.0 V0.1 VGeneral Description and
Operation, Fuel HO2S 1
C16Not UsedÐÐÐÐ

6E±339 ENGINE DRIVEABILITY AND EMISSIONS
0005
PCM Components
The PCM is designed to maintain exhaust emission levels
to government mandated standards while providing
excellent driveability and fuel efficiency. The PCM
monitors numerous engine and vehicle functions via
electronic sensors such as the throttle position (TP)
sensor, heated oxygen sensor (HO2S), and vehicle
speed sensor (VSS). The PCM also controls certain
engine operations through the following:

Fuel injector control

Ignition control module

Knock sensor

Automatic transmission shift functions

Cruise control

A/C clutch control
PCM Voltage Description
The PCM supplies a buffered voltage to various switches
and sensors. It can do this because resistance in the
PCM is so high in value that a test light may not illuminate
when connected to the circuit. An ordinary shop
voltmeter may not give an accurate reading because the
voltmeter input impedance is too low. Use a 10-megohm
input impedance digital voltmeter (such as J 39200) to
assure accurate voltage readings.
The input/output devices in the PCM include
analog-to-digital converters, signal buffers, counters,
and special drivers. The PCM controls most components
with electronic switches which complete a ground circuit
when turned ªON.º These switches are arranged in
groups of 4 and 7, called either a surface-mounted quad
driver module (QDM), which can independently control up
to 4 output terminals, or QDMs which can independently
control up to 7 outputs. Not all outputs are always used.
PCM Input/Outputs
Inputs ± Operating Conditions Read

Air Conditioning ªONº or ªOFFº
Engine Coolant Temperature

Crankshaft Position

Exhaust Oxygen Content

Electronic Ignition

Manifold Absolute Pressure

Battery Voltage

Throttle Position

Vehicle Speed

Fuel Pump Voltage

Power Steering Pressure

Intake Air Temperature

Mass Air Flow

Engine Knock

Camshaft Position
Outputs ± Systems Controlled

Exhaust Gas Recirculation (EGR)

Ignition Control

Fuel Control

Idle Air Control

Electric Fuel Pump

Air Conditioning

Diagnostics
± Malfunction Indicator Lamp (Service Engine Soon
lamp)
± Data Link Connector (DLC)
± Data Output

Transmission Control Module

Alternator Gain Control
PCM Service Precautions
The PCM is designed to withstand normal current draws
associated with vehicle operation. Avoid overloading any
circuit. When testing for opens and shorts, do not ground
or apply voltage to any of the PCM's circuits unless
instructed to do so. These circuits should only be tested
Tech-2. The PCM should remain connected to the PCM
or to a recommended breakout box.
Reprogramming The PCM
The Trooper allow reprogramming of the PCM without
removing it from the vehicle . This provides a flexible and
cost-effective method of making changes in software
calibrations.
The service programming system (SPS) will not allow
incorrect software programming or incorrect calibration
changes.
Refer to the UBS 98model year Immobilizer Workshop
Manual.
Throttle Position (TP) Sensor
The throttle position (TP) sensor is a potentiometer
connected to the throttle shaft on the throttle body. The
PCM monitors the voltage on the signal line and
calculates throttle position. As the throttle valve angle is
changed (accelerator pedal moved), the TP sensor signal
also changes. At a closed throttle position, the output of

00 Ð 12 SERVICE INFORMATION
10. ABNORMAL ENGINE NOISE
Checkpoint Possible cause Correction
Fuel Fuel unsuitable Replace the fuel
1. ENGINE KNOCKING
2. GAS LEAKAGE NOISE
Exhaust pipes Loosely connected exhaust pipes. Broken
exhaust pipesTighten the exhaust pipe
connections
Replace the exhaust pipes Check to see that the engine has been thoroughly warmed up before begining the troubleshooting
procedure.
Fuel injection timing Fuel injection timing improperly adjusted Adjust the fuel injection timing
Injection nozzle Improper injection nozzle starting pressure
and spray conditionAdjust or replace the injection
nozzle
Compression
pressureBlown out head gasket
Broken piston ringReplace the head gasket or the
piston ring
Injection nozzles
and/or glow plugsLoose injection nozzles and/or glow plugs Replace the washers
Tighten the injection nozzles and/or
the glow plugs
Exhaust manifold Loosely connected exhaust manifold and/or
glow plugsTighten the exhaust manifold
connections
Cylinder head gasket Damaged cylinder head gasket Replace the cylinder head gasket
3. CONTINUOUS NOISE
Fan belt Loose fan belt Readjust the fan belt tension
Cooling fan Loose coling fan Retighten the cooling fan
Water pump bearing Worn or damaged water pump bearing Replace the water pump bearing
Alternator or vacuum
pumpDefective alternator or vacuum pump Repair or replace the alternator or
the vacuum pump
Valve clearance Clearance improperly adjust Adjust the valve clearance

00 Ð 32 SERVICE INFORMATION
Drive Belt Adjustment
Check the drive belt tension.
Depress the drive belt mid-portion with a 98N (10kg/22 lb)
force.
Cooling Fan Pulley Drive Belt
Fan belt tension is adjusted by moving the alternator.
Depress the drive belt mid-portion with a 98N (10Kg/22lb)
force.
1Crankshaft damper pulley
2Alternator pulley
3Cooling fan pulley
Compressor Pulley Drive Belt
Move the idler pulley as required to adjust the compressor
drive belt tension.
If the vehicle is equipped with power steering, move the oil
pump as required.
Depress the drive belt mid-portion with a 98N (10Kg/22lb)
force.
1Crankshaft damper pulley
2Oil pump pulley or idler pulley
3Compressor pulley
Power Steering Oil Pump Pulley Drive Belt
Move the oil pump as required to adjust the oil pump drive
belt tension.
On air conditioner equipped models, both drive belts pulley
must always be replaced as a set.
Depress the drive mid-portion with a 98N (10kg/22 lb) force.
1Crankshaft damper pulley
2Oil pump pulley
3Compressor pulley or idler pulley Check the drive belt for cracking and other damage.
1Crankshaft damper pulley.
2Alternator pulley
3Cooling fan pulley
4Oil pump pulley or idler pulley
5Compressor pulley or idler pulley
10 (0.39)
mm(in) Drive Belt Deflection