Page 254 of 828

09-4
2. INSPECTION
1) Alternator Output Test
Item How to check DTC set value / Action
Output
current
B terminal
current
Rotor
coil
resistance
L terminal
voltage
Disconnect the cable connected to the
B terminal on the alternator. Connect
one end of the ammeter to the B
terminal and the other end to the cable
connected to the B terminal.
Measure the maximum output value.
(Maintain the engine speed between
2,500 and 3,000 rpm.)
(Turn the headlamp and all the electrical
switches on.) 1.
2.Pass: If the measured current is
45 A or higher.
Fail: If the measured current is
less than 45 A.
Check the current of the B
terminal. -
-
-
Move the gear selector lever to the
neutral position.
Maintain the engine speed at 2,500 rpm
with the vehicle unloaded.
(Turn all the electrical switches off.) 1.
2.Open circuit: If the measured
current is 5 A or higher. -
Disconnect the negative cable from the
battery.
Remove the B terminal and turn off the
ignition switch.
Measure the resistance between the L
and F terminals with an ohmmeter. 1.
2.
3.Pass: If the measured resistance
is between 3 and 6 Ω.
Faulty rotor coil or slip ring: If the
measured resistance is less than
3 Ω or greater than 6 Ω. -
-
Connect the B terminal wiring.
Measure the voltage with the engine
running. 1.
2.Specification: 12.5 V to 14.5 V
Faulty IC regulator or field coil: If
the measured voltage is 14.5 V
or higher. -
-
Disconnect the negative battery cable.
Connect the negative cable again after connecting the ammeter. -
-
Page 255 of 828

09-51451-01
2) Troubleshooting for Alternator
Item Cause Action
Overcharged
batteryDefective alternator voltage regulator
Replace the alternator
Defective voltage detection wiring Repair or replace
Loose alternator drive belt Adjust the belt tension or replace
Discharged batteryPoor connection of related circuit or
open circuitRetighten the loose connection or
repair open circuit
Defective alternator voltage regulator
Replace the alternator
Defective alternator voltage regulator
Replace the alternator
Terminated battery Replace the battery
Defective ground Repair
Charge warning
lamp does not
come on when
turning on ignition
switch with engine
stoppedDefective alternator voltage regulator
Replace the alternator
Open circuit in charge warning lamp,
fuse or wiringReplace or repair the charge
warning lamp or fuse
Defective ignition switch Replace the ignition switch
Defective ground of alternator circuit Repair
Charge warning
lamp is not turned
off after starting
engineDefective alternator voltage regulator
Replace the alternator
Corroded or worn battery cableRepair or replace the battery cable
Loose alternator drive belReplace the batteryAdjust the belt
tension or replace the belt
Defective wiring harness Repair or replace
Page 258 of 828

09-8
(3) Starting with jumper cable
If the battery is weak or terminated, the battery from another vehicle can be used with jumper
cables to start the engine.
Connecting order ▶
The positive (+) terminal of the discharged battery
The positive (+) terminal of the booster battery
The negative (-) terminal of the booster battery
Connect one end of the other jumper cable to the body of the discharged vehicle, such as the
engine block or a front towing hook. 1.
2.
3.
4.
Starting ▶
Prepare a set of jumper cables.
Place another vehicle that has the same 12 V of power near to the discharged vehicle.
Switch off all electrical accessories for the discharged vehicle.
Apply the parking brake and shift the transaxle to the P position (automatic transaxle) or neutral
(N) position (manual transaxle).
Connect the jumper cables.
Try to start the discharged vehicle while accelerating the engine rpm in the booster vehicle.
Attempt to start the engine with the discharged battery.
After starting the engine, carefully disconnect the jumper cables in the reverse sequence of
connection. 1.
2.
3.
4.
5.
6.
7.
8.
Page 260 of 828
09-10
Alternator
The alternator charges the battery and
supplies power to each electric unit by
converting the mechanical energy to the
electrical energy.
1. SYSTEM DESCRIPTION
1) Overview
The charge system is designed to supply electrical energy to the vehicle while driving, and
supplies a constant direct current voltage by converting mechanical rotational movement to
electrical energy.
The voltage regulator on the back of the alternator controls the generated voltage in all rotating
ranges and adjusts the system voltage according to the electric load and ambient temperature
change.
2) System Layout (Locations)
Battery
It converts the chemical energy to the
electrical energy and supplies power to
the corresponding electric units when
starting the engine.
Page 265 of 828
10-4
Glow plug control unit
(GCU)
1. OVERVIEW
The pre-heating system for D20DTR engine has the glow plug to the cylinder head (combustion
chamber), and improves the cold start performance and reduces the emission level.
The pre-heating resistor (air heater) is used to heat the intake air.
This enables the diesel fuel to be ignited in low temperature condition.
The ECU receives the information such as, engine rpm, coolant temperature, engine torque, etc.,
through CAN communication during pre-heating process; and the pre-heating control unit
controls the pre-heating, heating during cranking and post-heating by the PWM control.
Glow plug
Glow indicatorEngine ECU (D20DTR)
Page 268 of 828

10-71413-00
4) Operation
Glow plug is installed in the cylinder head. It enhances the cold starting performance and reduces
the exhaust gas during cold starting.
(1) Operation
Duty control area:
Between 5 and 100%
Frequency: 20 Hz
Duty ratio = (RMS voltage)²
(Battery voltage)² 1.
2.
3.
Pre-Glow: Step 1 ▶
If normal communication with the ECU is established 2 seconds after the power is supplied to the
IGN terminal from the battery, the GCU supplies the battery power to raise the temperature of the
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47009b008f008c0047008c0095008e00900095008c0047006c>CU before starting.
Pre-
heatingCoolant
temperature-30°C -25°C -20°C -10°C -5°C 0°C 20°C
Operating time
28 s 25 s 15 s 5 s 2 s 2 s 0 s
Operating
conditions- IGN: ON
- B+: below 15.2 VStop
conditions- Time-out
- IGN: OFF
- when engine cranking
If the input power (VB) is 11.5 V or less, the GCU supplies the battery power for arrival time
(T1).
If the input power (VB) is greater than 11.5 V, the GCU supplies the voltage of 11.5 V for arrival
time (T1). 1.
2.
- The time for pre-heating is controlled by the ECU.
The time for pre-heating by coolant temperature can vary slightly depending on e.g. other
vehicle operation elements.
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10-8
During cranking: Step 2 and step 3 ▶
Step 2: If the ECU receives the cranking signal after pre-heating (step 1), the GCU supplies the
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8c0047009b00960047005800530058005700570b450055>
Step 3: The GCU supplies the voltage of 5.1 V to keep the temperature at 1,000°C. 1.
2.
Under fixed temperature: The AQGS unit supplies power for 30 seconds (Step 1 + Step 3)
if no cranking signal is received after the step 1.
At cranking: The step 3 is started after the step 2. *
*
Post-glow: Step 4: ▶
The post-heating is for reducing HC/CO after the engine is started. If the time for post-heating
exceeds 180 sec., the GCU unit cuts off the power to each glow plug even if there is pre-heating
request from the engine ECU.
Post-
heatingOperating time
(approx.)-20°C -10°C 0°C 20°C 80°C
Operating time
(approx.)100 s 50 s 25 s 10 s 10 s
Emergency glow ▶
If no CAN signal is received for 4 seconds from the engine ECU after the IGN ON signal is input,
the GCU performs emergency preheat (Step 3) for 30 seconds.
P1 to P2: Pre glow
P3 to P4: Post glow
Page 271 of 828
11-4
2. TROUBLESHOOTING
ProblemPossible Cause Action
Engine will not
crankLow battery voltage Charge or replace
Loose, corroded or damaged battery cable
Repair or replace
Faulty starter or open circuit
Faulty ignition switch or blown fuse Repair or replace
Poor engine ground Repair
Engine cranks too
slowLow battery voltage Charge or replace
Loose, corroded or damaged battery cable
Repair or replace
Faulty starter
Starter does not
stopFaulty starter
Faulty ignition switch Replace
Engine cranks
normally, but does
not startBroken pinion gear or faulty starter
Replace the starter
Broken flywheel ring gear Replace
Open circuit Repair