Isuzu 4ja1 Instruction manual

WORKSHOP MANUAL
2011MY TF SERIES
ENGINE
4JA1/4JH1 MODELS
SECTION 6
Isuzu Motors Limited
E-Solutions &
Service Marketing Dept.

TROUBLESHOOTING 6 – 1
SECTION 6
TROUBLESHOOTING
TABLE OF CONTENTS
PAGE PAGE
BASIC INSPECTION PROCEDURE....6– 2
1. HARD STARTING............................6– 3
1-1.Starter Motor Inoperative ..........6– 3
1-2. Starter Motor Operates But
Engine Does Not Turn Over ...........6– 3
1-3. Engine Turns Over But Does
Not Start Engine..............................6– 4
2. UNSTABLE IDLING.........................6– 5
3. INSUFFICIENT POWER ..................6– 6
4. EXCESSIVE FUEL
CONSUMPTION..................................6– 7
5. EXCESSIVE OIL CONSUMPTION ..6– 8
6. OVERHEATING ...............................6– 9
7. WHITE EXHAUST SMOKE..............6– 9
8. DARK EXHAUST SMOKE...............6– 10
9. OIL PRESSURE DOES NOT RISE..6– 11
10. ABNORMAL ENGINE NOISE........6– 12
10-1. Engine Knocking ....................6– 12
10-2. Gas Leakage Noise.................6– 12
10-3. Continuous Noise ...................6– 13
10-4. Slapping Noise........................6– 13
10-5. Excessive Turbocharger
Noise ................................................6– 14
11. ROTATING PART WEAR OF
TURBOCHARGER..............................6– 14
12. OIL LEAKAGE FROM
TURBOCHRGER ................................6– 15
13. INSUFFICIENT ACCELERATION
AND/OR LACK OF POWER DUE
TO TURBOCHARGER........................6– 15
14. BATTERY CHARGING AND
NOISE PROBLEM ..............................6– 16
14-1. Battery No Charging...............6– 16
14-2. Battery Overcharging .............6– 16
14-3. Battery Under Charging .........6– 17
14-4. Battery Unstable Charging
Current.............................................6– 17
14-5. Charging System Noise .........6– 18
15. STARTER MOTOR PROBLEM .....6– 19
15-1. Starter Motor Pinion Engages
to Ring Gear But Engine Does
Not Turn Over..................................6– 19
15-2. Incorrect Pinion And Ring
Gear Engagement ...........................6– 19
15-3. Starter Motor Continues To
Run After The Starter Switch Is
Turned Off........................................6– 20
15-4. Excessive Commutator
Sparking ..........................................6– 20

6 – 2 TROUBLESHOOTING
Basic Inspection Procedure
Follow the under inspection procedure, when the problem vehicle comes workshop.
Step Inspection point Inspection result YES NO
1 Check the check engine lamp Is the check engine lamp turn
ON ?
Go to section
6E “On Board
Diagnostic
(OBD) System
Check" Go to Step 2
2 The battery fluid level and the
gravity
Was the problem found? Re-charge the
battery or
replace the
battery Go to Step 3
3 The engine coolant capacity Was the problem found? Replenish the
engine coolant Go to Step 4
4 The engine oil level Was the problem found? Replenish the
engine oil Go to Step 5
5 The air cleaner element Was the problem found? Clean or
replace Go to Step 6
6 The piping fixing condition (oil,
vacuum and fuel piping)
Was the problem found? Return normal
condition Go to Step 7
7 The drive belt tension and break Was the problem found? Re-adjust the
tension or
replace Go to Step 8
8 Go to section 6E “On Board
Diagnostic (OBD) System
Check”
Was the problem found?
Verify repair Go to Step 9
9 Go to mechanical
troubleshooting chart
Was the problem found?
Verify repair —

TROUBLESHOOTING 6 – 3
1. Hard Starting
Inspect the following items before diagnosis.
1. The battery conditions.
The terminal connection condition.
The battery charge condition or battery power weakness.
2. The fan belt loosen or broken.
3. The main fuse condition (open or not).
4. Fuel quantity level.
1–1 Starter motor inoperative
Step Action Value(s) Yes No
1 Check the starter switch.
Does the starter switch work?
—
Go to Step 2
Repair or
replace the
starter switch
2 Check the starter relay.
Does the starter relay work?
—
Go to Step 3
Repair or
replace the
starter relay
3 Check the magnetic switch.
Does the magnetic switch work?
—
Go to Step 4
Repair or
replace the
magnetic
switch
4 Check the pinion gear condition on the starter motor.
Was the condition normal?
—
Go to Step 5
Replace the
pinion gear
5 Check the brush wear or brush spring weakness.
Was the condition normal?
—
Replace the
starter motor
assembly
Repair or
replace the
brush or brush
spring
1-2 Starter motor operates but engine does not turn over
Step Action Value(s) Yes No
1 Check the engine internal seizure.
Was the engine seized?
—
Repair or
replace seized
parts
Check other
DTC by Tech
2 and go to
indicated DTC

6 – 4 TROUBLESHOOTING
1-3 Engine turn over but does not start engine
Incase of the fuel not being delivered to the injection pump
Step Action Value(s) Yes No
1 Check clogged, damaged the fuel piping or the
connector loosen.
Was any problem found?
—
Repair replace
problem parts. Go to Step 2
2 Was the over flow valve on the fuel filter closed? —Repair replace
the over flow
valve Go to Step 3
3 Was the fuel filter element clogged? —Replace the
fuel filter
element Go to Step 4
4 Was the fuel line air bled? —Go to Step 5 Bleed the air
5 Are any DTC stored? —Go to indicated
DTC Solved
Incase of the fuel is being delivered to the injection pump
Step Action Value(s) Yes No
1 Was the water contain in the fuel? —Replace the
fuel Go to Step 2
2 Was the fuel line air bled? —Go to Step 3 Bleed the air
3 Was the injection spray condition complete? —
Go to Step 4
Replace the
injection nozzle
4 Was the injection nozzle injection starting pressure
OK?
(See below)
Go to Step 5
Replace the
injection nozzle
5 Was the injection nozzle sticking? —Replace the
injection nozzle Go to Step 6
6 Are any DTC stored? —Go to indicated
DTC Solved
Injection nozzle opening pressure
1st = 19.5 MPa (199 kg/cm
2
, 2828 psi)

TROUBLESHOOTING 6 – 5
2. Unstable Idling
Step Action Value(s) Yes No
1 Was the fuel line air bled completely? —Go to Step 3 Bleed the air
2 Was the fuel line leakage or blockage found? —Repair or
replace relation
parts. Go to Step 4
3 Was the water contained in the fuel? —Replace the
fuel Go to Step 5
4 Was the fuel filter element clogged? —Replace the
fuel filter
element Go to Step 6
5 Was the injection starting pressure or the injection
spray condition OK?
(See below)
Go to Step 7
Replace the
injection nozzle
6 Was the injection nozzle sticking? See Step 6 Replace the
injection nozzle Go to Step 8
7 Check the throttle valve condition.
Was the idling port clogged in the throttle valve?
—Repair or
replace the
throttle valve Go to Step 9
8 Was the valve clearance improper adjusted? 0.4 mm
(0.016 in)
both intake
and exhaust
valves
Adjust the
valve clearance Go to Step 10
9 Was the compression pressure OK? 3.0MPa (31.0
kg/cm
2
, 441
psi) at
200rpm
Go to Step 11
Readjust the
valve clearance
or replace the
cylinder head
gasket or
cylinder liner or
piston or piston
ring or valve
and valve seat
10 Are any DTC stored? —Go to indicated
DTC Solved
Injection nozzle opening pressure
1st = 19.5 MPa (199 kg/cm
2
, 2828 psi)

6 – 6 TROUBLESHOOTING
3. Insufficient Power
Step Action Value(s) Yes No
1 Was the air cleaner element condition OK? (Clogged
or not)
—
Go to Step 2
Clean or
replace the air
cleaner
element.
2 Was the intake air leakage found from intake
system?
—Repair or
replace the
intake air
system. Go to Step 3
3 Was the fuel filter element condition OK? (Clogged
or not)
—
Go to Step 4
Clean or
replace the fuel
filter element.
4 Check the fuel injection pipes.
Does the injection pipes have obstruction or any
damage?
—Repair or
replace the fuel
injection pipes. Go to Step 5
5 Was the water contained in the fuel? —Replace the
fuel Go to Step 6
6 Was the injection nozzle pressure or spray pattern
normal?
—
Go to Step 7
Readjust the
injection nozzle
pressure or
replace the
nozzle.
7 Was the compression pressure OK? 3.0 MPa
(31.0 kg/cm
2
,
441 psi) at
200 rpm
Go to Step 8
Readjust the
valve clearance
or replace the
cylinder head
gasket or
cylinder liner or
piston or piston
ring or valve
and valve seat
8 Was the exhaust pipe clogged? —Repair or
replace the
exhaust pipe. Go to Step 9
9 Was the exhaust gas leakage found from exhaust
system?
—Repair or
replace the
exhaust
system. Go to Step 10
10 Was the waste gate control actuator hose broken or
cracked?
—Replace the
hose. Go to Step 11
11 Was the waste gate working completely? —
Go to Step 12
Replace the
turbocharger
assembly.
12 Was turbocharger working completely? —
Go to Step 13
Replace the
turbocharger
assembly.
13 Are any DTC stored? —Go to indicated
DTC Solved

TROUBLESHOOTING 6 – 7
4. Excessive Fuel Consumption
Step Action Value(s) Yes No
1 Was the air cleaner element clogged? —Clean or
replace the air
cleaner
element. Go to Step 2
2 Was the air leakage found from the air intake side of
the turbocharger?
—Repair or
replace the air
intake side of
the
turbocharger. Go to Step 3
3 Was the turbocharger working completely? —
Go to Step 4
Replace the
turbocharger
4 Was there the fuel leakage? —Repair or
replace the fuel
leakage part. Go to Step 5
5 Was the compression pressure OK? 3.0 MPa
(31.0 kg/cm
2
,
441 psi) at
200 rpm
Go to Step 6
Readjust the
valve clearance
or replace the
cylinder head
gasket or
cylinder liner or
piston or piston
ring or valve
and valve seat
6 Was the injection nozzle pressure or spray pattern
normal?
—
Go to Step 7
Replace the
injection nozzle
7 Are any DTC stored? —Go to indicated
DTC Solved

6 – 8 TROUBLESHOOTING
5. Excessive Oil Consumption
Step Action Value(s) Yes No
1 Does the air cleaner element conditon OK? (Clogged
or not)
—
Go to Step 2
Clean or
replace the air
cleaner
element
2 Does PCV (Positive Crankcase Ventilation) Valve
has problem?
—Repair or
replace the
relation parts. Go to Step 3
3 Was the oil pressure value more than normal value? Less than
588 kPa (6.0
kg/cm
2
, 85
psi)
Repair or
replace the oil
relief valve Go to Step 4
4 Inspect the front and rear crankshaft oil seal.
Was the oil leakage found?
—Replace the
failure part. Go to Step 5
5 Was the oil leakage found from any gasket? —Replace the
wrong gasket Go to Step 6
6 Inspect the valve stem seal, the valve stem and the
valve guide for worn.
Were any worn found?
—
Replace the
worn part. Go to Step 7
7 Was the oil leakage found from the turbocharger oil
seal?
—Replace the oil
seal. Go to Step 8
8 Was the oil drain pipe of the turbocharger restricted? —Repair or
replace the oil
drain pipe. Go to Step 9
9 Was the oil drain passage in the turbocharger center
housing restricted?
—Clean the
center housing Go to Step 10
10 Does turbine wheel has any impact damage? —Replace the
turbocharger Go to Step 11
11 Are any DTC stored? —Go to indicated
DTC Solved

TROUBLESHOOTING 6 – 9
6. Overheating
Step Action Value(s) Yes No
1 Was the engine coolant level OK? —
Go to Step 2
Replenish the
coolant
2 Was the water leakage or the radiator restriction
found? (Include radiator cap)
—Repair or
replace the
leakage part. Go to Step 3
3 Was the fan belt slippage found? —Tension or
replace the fan
belt. Go to Step 4
4 Was the fan clutch working completely? —
Go to Step 5
Replace the fan
clutch
assembly.
5 Was the oil leakage found from fan clutch? —Replace the fan
clutch
assembly Go to Step 6
6 Was the thermostat working normally? —
Go to Step 7
Replace the
thermostat.
7 Was the water pump working OK? —
Go to Step 8
Replace the
water pump
assembly.
8 Was the restriction by the foreign materials in the
cooling system found? For example, clog the water
hose between the cylinder body and radiator etc..
—Clean or
replace the
clog part. Go to Step 9
9 Was the water leakage found from the sealing cap
on the cylinder body?
—Replace the
sealing cap or
replace the
cylinder body. Go to Step 10
10 Are any DTC stored? —Go to indicated
DTC. Solved
7. White Exhaust Smoke
Step Action Value(s) Yes No
1 Was the compression pressure OK? 3.0 MPa
(31.0 kg/cm
2
,
441 psi) at
200 rpm
Go to Step 2
Readjust the
valve clearance
or replace the
cylinder head
gasket or
cylinder liner or
piston or piston
ring or valve
and relation
parts.
2 Was the PCV (Positive Crankcase Ventilation) valve
working completely?
—
Go to Step 3
Repair or
replace the
PCV valve.
3 Was the turbocharger working completely? —
Go to Step 4
Replace the
turbocharger.
4 Are any DTC stored? —Go to indicated
DTC Solved

6 – 10 TROUBLESHOOTING
8. Dark Exhaust Smoke
Step Action Value(s) Yes No
1 Was the air cleaner element normal condition? —
Go to Step 2
Clean or
replace the air
cleaner
element
2 Was the EGR valve sticking? —Replace the
EGR valve Go to Step 3
3 Was the injection nozzle pressure or the injection
spray pattern OK?
—
Go to Step 4
Replace the
injection nozzle
4 Was the oil leakage found from the turbocharger oil
seal?
—Replace the oil
seal Go to Step 5
5 Was the oil drain pipe of the turbocharger restricted? —Repair or
replace the oil
drain pipe Go to Step 6
6 Was restricted the oil drain passage in the
turbocharger center housing restricted?
—Clean the
center housing Go to Step 7
7 Does turbine wheel has any impact damage? —Replace the
turbocharger Go to Step 8
8 Does PCV (Positive Crankcase Ventilation) Valve
has problem?
—Repair or
replace the
relation parts Go to Step 9
9 Are any DTC stored? —Go to indicated
DTC Solved

TROUBLESHOOTING 6 – 11
9. Oil Pressure Does Not Rise
Step Action Value(s) Yes No
1 Was the oil pressure warning lamp working OK? —
Go to Step 2
Replace the oil
pressure
warning lamp
2 Does the oil filter element clog? —Replace the oil
filter element Go to Step 3
3 Does the relief valve open? —Repair or
replace the
relief valve Go to Step 4
4 Does the oil strainer clog? —Clean or
replace the oil
strainer Go to Step 5
5 Was the oil pump working OK? (The pump related
parts worn etc.)
—
Go to Step 6
Repair or
replace the oil
pump.
6 Was the rocker arm and/or relation parts worn? —Replace the
rocker arm
and/or relation
parts Go to Step 7
7 Was the camshaft and/or relation parts worn? —Replace the
camshaft
and/or relation
parts Go to Step 8
8 Was the crankshaft and/or relation parts worn? —Replace the
crankshaft
and/or relation
parts Go to Step 9
9 Are any DTC stored? —Go to indicated
DTC Solved
Table of pressure unit
Pressure kPa (kg/cm
2
) 100
(1.0)
980
(10.0)
Resistance ohm 81 30
Electric current A 63.5 106.7

6 – 12 TROUBLESHOOTING
10. Abnormal Engine Noise
10–1 Engine knocking
Step Action Value(s) Yes No
1 Was the injection nozzle pressure or injection spray
pattern OK?
—
Go to Step 2
Replace the
injection nozzle
2 Was the compression pressure OK? 3.0 MPa
(31.0 kg/cm
2
,
441 psi) at
200 rpm Go to Step 3
Replace the
cylinder head
gasket or
piston ring
3 Are any DTC stored? —Go to indicated
DTC Solved
10–2 Gas leakage noise
Step Action Value(s) Yes No
1 Was the exhaust pipe loose or broken? —Retighten or
replace the
exhaust pipe Go to Step 2
2 Was the exhaust manifold loose? —
Retighten or
replace the
exhaust
manifold. Or
replace the
exhaust
manifold gasket Go to Step 3
3 Was the injection nozzle loose? —Retighten or
replace the
injection nozzle
fixing bolt Go to Step 4
4 Was the cylinder head gasket broken? —Replace the
cylinder head
gasket Go to Step 5
5 Are any DTC stored? —Go to indicated
DTC Solved

TROUBLESHOOTING 6 – 13
10–3 Continuous noise
Step Action Value(s) Yes No
1 Was the fan belt tension OK? 9 –13 mm
(0.35 –0.51
in)
Go to Step 2
Adjust the fan
belt tension.
2 Was the cooling fan loose? —Tighten the
cooling fan Go to Step 3
3 Was noise coming from the generator? —Repair or
replace the
generator
and/or the
vacuum pump Go to Step 4
4 Was noise coming from the water pump? —Replace the
water pump Go to Step 5
5 Was noise coming from the cylinder head cover? —Readjust the
valve
clearance. Go to Step 6
6 Are any DTC stored? —Go to indicated
DTC Solved
10-4 Slapping noise
Step Action Value(s) Yes No
1 Was noise coming from the cylinder head cover? —Go to Step 2 Go to Step 4
2 Were valve clearances correct? 0.4 mm
(0.016 in)
both intake
and exhaust
Adjust the
valve
clearances Go to Step 3
3 Were the rocker arms damaged? —Replace the
rocker arms Go to Step 4
4 Was the flywheel fixing bolt loose? —Tighten the
fixing bolt. Go to Step 5
5 Was noise coming from the cylinder body? —Go to Step 6 Go to Step 10
6 Inspect the crankshaft bearing and/or crankshaft.
Was the crankshaft bearing and/or crankshaft worn?
—Replace the
worn parts Go to Step 7
7 Inspect the connecting rod bearing and/or crankpin.
Was the connecting rod bearing and/or crankpin
worn?
—
Replace the
worn parts Go to Step 8
8 Inspect the connecting rod small end bushing and/or
piston pin.
Was the connecting rod small end bushing and/or
piston pin worn?
—
Replace the
worn parts Go to Step 9
9 Inspect the piston and/or cylinder liner.
Was the piston and/or cylinder liner worn or
damaged?
—Replace the
worn or
damaged parts Go to Step 10
10 Are any DTC stored? —Go to indicated
DTC Solved

6 – 14 TROUBLESHOOTING
10-5 Excessive turbocharger noise
The vibration noise (the air aspiration noise) occurred when turbocharger rotates, it is normal condition of the
turbocharger, no necessary any actions.
Step Action Value(s) Yes No
1 Was the excessive noise coming from the
turbocharger?
—
Go to Step 2 Go to Step 10
2 Inspect the fixing bolts and bands.
Was any problem found?
—Tighten the
loose parts Go to Step 3
3 Was the intake or exhaust system gasket damaged? —Replace the
damaged
gasket. Go to Step 4
4 Inspect rotation parts condition.
Was the turbine wheel rotation rough?
—Replace the
turbocharger. Go to Step 5
5 Inspect the turbine wheel.
Was the turbine wheel rubbing against housing?
—Replace the
turbocharger. Go to Step 6
6 Was the turbine wheel damaged? —Replace the
turbocharger. Go to Step 7
7 Were there carbon deposits in the turbine or
compressor housing?
—Clean or
replace the
turbocharger. Go to Step 8
8 Inspect the oil supply condition.
Was the oil feed pipe clogged?
—Repair or
replace the oil
feed pipe. Go to Step 9
9 Was the turbine shaft bearing worn? —Replace the
turbocharger. Go to Step 10
10 Are any DTC stored? —Go to indicated
DTC Solved
11. Rotating Part Wear of Turbocharger
Step Action Value(s) Yes No
1 Inspect engine oil.
Was it contaminated with foreign materials?
—Replace the
engine oil Go to Step 2
2 Was the recommended engine oil grade/viscosity
being used?
API CD or
ISUZU
genuine/
10W–30
Go to Step 3
Replace the
engine oil
3 Was the oil feed pipe restricted? —Clean or
replace the oil
feed pipe Go to Step 4
4 Was the oil seal of turbocharger defective? —Replace the oil
seal Go to Step 5
5 Was the center housing oil drain passage clogged? —Clean center
housing or
replace the
turbocharger Go to Step 6
6 Was there oil sludge and/or coking on the turbine
shaft?
—Replace the
turbocharger Go to Step 7
7 Are any DTC stored? —Go to indicated
DTC Solved

TROUBLESHOOTING 6 – 15
12. Oil Leakage from Turbocharger
Step Action Value(s) Yes No
1 Inspect the oil leakage area.
Was the oil feed pipe eye bolt loose or the gasket
broken?
—Tighten the eye
bolt or replace
the gasket. Go to Step 2
2 Were the V band fixing faces tight? —Tighten band or
replace the
turbocharger Go to Step 3
3 Was there oil leakage from the flange of the turbine
housing?
—Replace the
turbocharger Go to Step 4
4 Was there oil leakage from the flange of compressor
housing?
—Tighten the bolt
and/or hose
clamp. Go to Step 5
5 Are any DTC stored? —Go to indicated
DTC Solved
13. Insufficient Acceleration and/or Lack of Power due to turbocharger
Step Action Value(s) Yes No
1 Inspect the air or exhaust route.
Was the air and/or exhaust gas piping loose?
—Tighten flange
bolts or hose
clamp. Go to Step 2
2 Inspect the work of waste gate valve control.
Was there rust on the linkage rod or pin of the waste
gate valve?
—
Replace the
turbocharger Go to Step 3
3 Was air leakage found from the actuator piping? —Repair or
replace the
actuator pipe or
hose/ Go to Step 4
4 Inspect the inside of the turbocharger.
Was the turbine shaft end nut loose?
—Replace the
turbocharger Go to Step 5
5 Were the turbine blades bent? —Replace the
turbocharger Go to Step 6
6 Was the turbine wheel rubbing against housing? —Replace the
turbocharger Go to Step 7
7 Are any DTC stored? —Go to indicated
DTC Solved

6 – 16 TROUBLESHOOTING
14. Battery Charging and Noise Problem
Visual/physical check the following items before diagnosis.
The drive belt tension.
The battery terminals connection condition.
The ground connection condition.
The generator and the battery fastener condition.
The battery fluid level and specific gravity.
14-1 Battery No Charging
Step Action Value(s) Yes No
1 Was “Visual/Physical Check" performed. —
Go to Step 2
Go to
visual/physical
check
2 Inspect the brush contact condition on the generator.
Was there poor contact between the brush and the
slip ring?
—Repair or
replace the
brush and/or
the slip ring. Go to Step 3
3 Inspect the stator coil on the generator.
Was there an open circuit or the scorching on the
stator coil?
—
Replace the
stator coil. Go to Step 4
4 Inspect the rotor coil on the generator.
Was there an open circuit or the scorching on the
rotor coil?
—
Replace the
rotor coil. Go to Step 5
5 Inspect the rectifier on the generator.
Was the rectifier defective?
—Replace the
rectifier Go to Step 6
6 Inspect the IC regulator.
Was the IC regulator defective?
—Replace the IC
regulator. Go to Step 7
7 Are any DTC stored? —Go to indicated
DTC. Solved
14-2 Battery Overcharging
Step Action Value(s) Yes No
1 Was “Visual/Physical Check" performed. —
Go to Step 2
Go to
visual/physical
check
2 Inspect the terminal circuit.
Were the B and F terminals shorted?
—Repair the
short circuit. Go to Step 3
3 Check the regulating voltage.
Was the IC regulator voltage excessive?
—Replace the IC
regulator. Go to Step 4
4 Are any DTC stored? —Go to indicated
DTC. Solved

TROUBLESHOOTING 6 – 17
14-3 Battery Under Charging
Step Action Value(s) Yes No
1 Was “Visual/Physical Check" performed. —
Go to Step 2
Go to
visual/physical
check
2 Inspect the brush contact condition on the generator.
Was there intermittent contact between the brush
and the slip ring?
—Repair or
replace the
brush holder
assembly. Go to Step 3
3 Inspect the rotor coil on the generator.
Was there a short circuit in the rotor coil?
—Repair or
replace the
rotor coil. Go to Step 4
4 Inspect the stator coil on the generator.
Was there an open circuit or the short circuit on the
stator coil?
—Repair or
replace the
stator coil. Go to Step 5
5 Inspect the rectifier on the generator.
Was the rectifier defective?
—Replace the
rectifier Go to Step 6
6 Inspect the IC regulator on the generator.
Was the IC regulator defective?
—Replace the IC
regulator. Go to Step 7
7 Was the electrical load excessive? —Replace more
higher capacity
generator. Go to Step 8
8 Are any DTC stored? —Go to indicated
DTC. Solved
14-4 Battery Unstable Charging Current
Step Action Value(s) Yes No
1 Was “Visual/Physical Check" performed. —
Go to Step 2
Go to
visual/physical
check
2 Inspect the brush contact condition on the generator.
Was there poor contact between the brush and the
slip ring?
—Repair or
replace the
brush and/or
the slip ring. Go to Step 3
3 Inspect the rotor coil on the generator.
Was there the short circuit or an open circuit in the
rotor coil?
—Repair or
replace the
rotor coil. Go to Step 4
4 Inspect the stator coil on the generator.
Was there an open circuit or the short circuit in the
stator coil?
—Repair or
replace the
stator coil. Go to Step 5
5 Inspect the connection between the rectifier and
stator coil on the generator.
Was there a loose connection between the rectifier
and stator coil ?
—
Repair the
loose
connection. Go to Step 6
6 Inspect the IC regulator on the generator.
Was the IC regulator defective?
—Replace the IC
regulator. Go to Step 7
7 Are any DTC stored? —Go to indicated
DTC. Solved

6 – 18 TROUBLESHOOTING
14-5 Charging System Noise
Step Action Value(s) Yes No
1 Was “Visual/Physical Check" performed. —
Go to Step 2
Go to
visual/physical
check
2 Was there intermittent noise or continuous noise and
that could be identified clearly by increasing and
decreasing engine speed?
—
Replace the
bearing. Go to Step 3
3 Was there a growling sound and does this sound
stop when the connector was disconnected?
—Replace the
stator coil. Go to Step 4
4 Was intermittent sound heard when the generator
was running?
—Replace the
brush and/or
slip ring. Go to Step 5
5 Was frictional sound heard when generator was
running?
—Clean the slip
ring or replace
the brush. Go to Step 6
6 Are any DTC stored? —Go to indicated
DTC. Solved