Sakai R2-4, Shop Manual

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10-029
TROUBLESHOOTING
2-4. Propulsion System
Check following items before troubleshooting.
No blown fuses and power is applied up to fuses.
when measuring voltage and current without disconnecting connectors, refer to “Measuring voltage and current
flowing using tester” (P.10-006 to P.10-008).
Check any ground circuit which belongs to components to be checked.
2-4-1. Machine moves neither forward nor backward 1/2
Parking brake switch must be released.
Foot brake switch must be ON (Brake pedal is not depressed).
Reference Fig.: 2-4-1
Check point Check/Cause Action
1. Parking Brake Solenoid Disconnect harness and measure resistance of coil.
Standard resistance : 8.5 Ω
If measured resistance is abnormal, parking brake
solenoid is faulty.
•
•
Replace parking brake
solenoid.
2. Propulsion Pump
Neutral Solenoid
Disconnect harness and measure resistance of coil.
Standard resistance : 8.5 Ω
If measured resistance is abnormal, propulsion pump
neutral solenoid is faulty.
•
•
Replace propulsion
pump neutral solenoid.
3. Brake Relay (1) when starter switch is ON, measure voltage between
brake relay terminal 1 inlet wire BW and chassis
ground.
Standard voltage : 12 V or more
(2) when starter switch is ON, measure voltage between
brake relay terminal 3 inlet wire GW and chassis
ground.
Standard voltage : 12 V or more
(3) when starter switch is ON, measure voltage between
brake relay terminal 5 outlet wire BrB and chassis
ground.
Standard voltage : 12 V or more
If above items (1) and (2) are OK and item (3) is NG,
brake relay is faulty.
•
Replace brake relay.
4. Foot Brake Switch (1) when starter switch is ON, measure voltage between
foot brake switch terminal COM inlet wire wB and
chassis ground.
Standard voltage : 12 V or more
(2) when starter switch is ON, measure voltage between
foot brake switch terminal NO outlet wire Bw and
chassis ground.
Standard voltage : 12 V or more
If above item (1) is OK and item (2) is NG, foot brake
switch is faulty.
•
Replace foot brake
switch.
5. Parking Brake Switch (1) when starter switch is ON, measure voltage between
parking brake switch terminal 1 inlet wire WB and
chassis ground.
Standard voltage : 12 V or more
(2) when starter switch is ON, measure voltage between
parking brake switch terminal 3 outlet wire GW and
chassis ground.
Standard voltage : 12 V or more
If above item (1) is OK and item (2) is NG, parking brake
switch is faulty.
•
Replace parking brake
switch.
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