Skyjack SJ20, Service Manual

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SJ20 238886ABA
Section 4 – Troubleshooting Information Electrical System
4.2-2 No Lift or Steer Functions
1. Loose or broken wire 19 from motor contactor C1
coil negative to machine controller pin A27
Check continuity. Replace if defective.
2. Defective motor contactor C1 Replace if defective
3. Loose or broken wire 03B from motor contactor
C1 N.O. contact to machine controller B+
Check continuity. Replace if defective.
4. Loose or broken wire 03B from machine
controller B+ to pump motor positive terminal
Check continuity. Replace if defective.
5. Loose or broken ground wire from machine
controller P- to pump motor negative terminal
Check continuity. Replace if defective.
6.
Loose or broken wire 03B from motor contactor
C1 N.O. contact to circuit breaker CB2
Check continuity. Replace if defective.
7. Defective or tripped circuit breaker CB2
Check for short circuits, Reset Circuit Breaker.
Replace breaker if defective.
8. Loose or broken wire 03C from circuit breaker
CB2 to machine controller pin B19
Check continuity. Replace if defective.
9. Loose or broken wire 03C from circuit breaker
CB2 to lift (3H-14), right steer (4H-23) and left
steer (4H-24) coils
Check continuity. Replace if defective.
4.2-3 No Lift from Base or Platform
1. Loose or broken wire 14 from lift coil 3H-14 to
machine controller pin A25
Check continuity. Replace if defective.
2. Defective coil 3H-14 Replace coil
18. Open or defective upper controll box E-stop switch S4 Close switch. Replace if defective
19. Loose or broken wire 08 from upper control box E-Stop
switch S4 to machine controller pin A7
Check continuity. Replace if defective.
20. Loose or broken wire 00 from machine controller B- to
battery negative
Check continuity. Replace if defective.
21. Loose or broken wire #08C from base key switch S10
to upper control box joystick pin P-16 and/or service
position position limit switch LS3
Check continuity. Replace if defective.
22. Misadjusted or defective service position position
limit switch LS3
Adjust switch. Replace if defective
23. Loose or broken wire 51 from service position
position limit switch LS3 to control box joystick
pin P-18
Check continuity. Replace if defective.