Battery Charging System; Inspection Of Alternator; Inspection Of Rectifier - TOHATSU MFS25 Service Manual

Electrical System

7.Battery Charging System

1) Inspection of Alternator

1. Disconnect alternator coupler (3 pin).
2. Measure alternator resistance. Replace if other than
specified value.
This test can be made without removing parts.
Alternator (Charge Coil) Resistance : Reference Value (at 20°C)
Between Yellow (Y) and Yellow (Y) (three types)
0.29 to 0.43 Ω

2) Inspection of Rectifier

• Check wire harness for disconnection of lead wire and
defective connection.
• Check conductivity between each point by referring to the
following table. Value in ( ) is reference value.
• Perform the measurement with all connections
disconnected to make the component a separated unit.
This test can be made without removing parts.
Rectifier Tester Check Chart
Red
Yellow
Black
Yellow
Yellow
• Measurement Conditions : Type of Circuit Tester : HIOKI3030
• Measurement Range : 1kΩ
• Permissible Error of Resistance : ±20%
• : The resistance values may vary widely
among circuit testers because of their error
characteristics.
Note : 1 It is recommended to use "HIOKI HiTESTER MODEL 3030" for this measurement. Use of other instrument
model for the measurement can cause indication of abnormal value for normal condition, resulting in inaccurate
measurement.
2 Disconnect all connections, and measure as an independent unit.
3 Any movement of pointer indicates "ON" or "conductive" state.
4 "CON" means that the pointer moves once and then returned to the value shown in ( ) because of characteristic
of capacitor.
5 The value in ( ) is the condition applied when "1kΩ" range is used. The measurement varies widely among types
of instrument, situations (such as inner power supply), or measurement ranges due to diodes used in the unit.
8-24
"ON" means "conductive", and "OFF" means "non-conductive".
Tester Lead Positive (+) Side (Red)
Red Yellow
OFF
CON
( ∞ )
ON
(5kΩ)
ON ON
(6kΩ) (2.5kΩ)
ON ON
(5kΩ) (5kΩ)
ON ON
(5kΩ) (5kΩ)
2
1
1 Alternator (3 Pin) (Charge Coil)
2 Alternator (6 Pin) (Exciter Coil, ECU/Charge Coil)
Black Yellow
OFF OFF
CON
( ∞ ) ( ∞ )
ON ON
(2.5kΩ) (5kΩ)
ON
(2.5kΩ)
ON
(2.5kΩ)
ON ON
(2.5kΩ) (5kΩ)
Yellow
OFF
CON
( ∞ )
ON
(5kΩ)
ON
(2.5kΩ)
ON
(5kΩ)
25/30 2006