Mitsubishi L200. Manual — part 218

CHARGING SYSTEM

ENGINE ELECTRICAL

16-2

CHARGING SYSTEM

GENERAL INFORMATION

M1161000102045

The charging system uses the alternator output to
keep the battery charged at a constant level under
various electrical loads.
OPERATION

AK400075

Voltage

Time

Approximately
14.4 V

AB

Rotation of the excited field coil generates AC volt-
age in the stator.
This alternating current is rectified through diodes to
DC voltage having a waveform shown in the illustra-
tion.
The average output voltage fluctuates slightly with
the alternator load condition.

When the ignition switch is turned on, current flows in
the field coil and initial excitation of the field coil
occurs.
When the stator coil begins to generate power after
the engine is started, the field coil is excited by the
output current of the stator coil.
The alternator output voltage rises as the field cur-
rent increases and it falls as the field current
decreases. When the battery voltage (alternator "S"
terminal voltage) reaches a regulated voltage of
approximately 14.4 V, the field current is cut off.
When the battery voltage drops below the regulated
voltage, the voltage regulator regulates the output
voltage to a constant level by controlling the field cur-
rent.
In addition, when the field current is constant, the
alternator output voltage rises as the engine speed
increases.

CAUTION

When the specified alternator is not used, each
ECU would probably fail.

CHARGING SYSTEM

ENGINE ELECTRICAL

16-3

<Except Euro 5>

AK403859

+

–

B

S
L

AB

Alternator

Stator
coil

Voltage
regulator

Ignition
switch

Battery

Field coil

Charging
warning lamp

Combination
meter

<Euro 5>

AK802592AE

Battery

Charging
warning lamp

Ignition
switch-IG

Combination
meter

B

S
L

G

FR

Engine-ECU

Alternator

Stator coil

Stator coil

Voltage
regulator

Field coil

ALTERNATOR SPECIFICATIONS

Item

Except Euro 5

Euro 5

Type

Battery voltage sensing

Battery voltage sensing

Rated output V/A

12/90 <Standard>
12/120 <Cold climate zone>

12/95 <Standard>
12/130 <Cold climate zone>

Voltage regulator

Electronic built-in type

Electronic built-in type

CHARGING SYSTEM

ENGINE ELECTRICAL

16-4

SERVICE SPECIFICATIONS

M1161000301370

Item

Standard value

Limit

Alternator output line voltage drop (at 30 A) V

−

Maximum 0.3

Regulated voltage ambient
temperature at voltage regulator
(vehicle stationary) V

−20°C

14.2

− 15.4

−

20

°C

13.9

− 14.9

−

60

°C

13.4

− 14.6

−

80

°C

13.1

− 14.5

−

Output current

−

70 % of normal output current

CHARGING SYSTEM

ENGINE ELECTRICAL

16-5

SPECIAL TOOL

M1161000600646

Tool

Number

Name

Use

MB991910

MB991826

MB991955

MB991911

MB991824

MB991827

MB991825

A

B

C

D

E

F

DO NOT USE

MB991955
A:
MB991824
B:
MB991827
C:
MB991910
D:
MB991911
E:
MB991825
F:
MB991826

M.U.T.-III sub assembly

• A: Vehicle

communication
interface (V.C.I.)

• B: M.U.T.-III USB

cable

• C: M.U.T.-III main

harness A (Vehicles
with CAN
communication
system)

• D: M.U.T.-III main

harness B (Vehicles
without CAN
communication
system)

• E: M.U.T.-III

measurement adapter

• F: M.U.T.-III trigger

harness

• Checking the engine speed

For vehicles with CAN
communication, use M.U.T.-III main
harness A to send simulated
vehicle speed. If you connect
M.U.T.-III main harness B instead,
the CAN communication does not
function correctly.

MB991519

Alternator test harness

Checking the alternator
("S" terminal voltage)

CAUTION