Skyjack SJ20, Service Manual

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SJ20 238886ABA
Section 4 – Troubleshooting Information Electrical System
NOTE
The MEWP functions may be disabled by the load sense system. Please first make sure that the mast is fully
retracted, the platform is free of added weight and there are no faults in the load sense system.
The MEWP functions may be disabled by the machine control system. Check for any codes displayed and
refer the code chart in section
5.2-1 Skycoded Display Messages . .
4.2 Electrical System
4.2-1 All Controls Inoperative
1. Battery cables loose/disconnected Tighten or connect battery cables
2. Battery Discharged or Defective Charge battery or replace if defective
3. Fuse F1 defective or open
Replace fuse.
4. Loose or broken B+ cable 03 from batteries to battery
disconnect switch S1
Check continuity. Replace if defective.
5. Open or defective battery disconnect switch S1 Close switch. Replace if defective
6. Loose or broken wire #03A from battery disconnect
switch S1 to motor contactor C1 common
Check continuity. Replace if defective
7. Loose or broken wire #03A from motor contactor C1 to
circuit breaker CB1
Check continuity. Replace if defective
8. Circuit breaker CB1 tripped or defective.
Reset breaker, check for defective wiring. Replace
if defective.
9. Loose or broken wire #05 from circuit breaker CB1 to
base emergency stop switch S28.
Check continuity. Replace if defective.
10. Open or defective base emergency stop switch S28.
Close switch. Replace if defective.
11. Loose or broken wire #05A from base emergency stop
switch S3 to base key switch S10.
Check continuity. Replace if defective.
12. Loose or broken #05A wires between base key switch
S10 terminals
Check continuity. Replace if defective.
13. Open or defective key select switch S10
Close switch. Replace if defective
14. Loose or broken wire #08C from base key switch S10
to motor contactor C1 coil +
Check continuity. Replace if defective.
15. Loose or broken wire #08C from motor contactor C1
coil + to machine controller pin A3.
Check continuity. Replace if defective.
16. Loose or broken wire 07 from base key switch to
machine controller pin B12
Check continuity. Replace if defective.
17. Loose or broken wire 07 from base key switch to upper
control box E-Stop switch S4
Check continuity. Replace if defective.