GE PANDA Service Manual page 103

Possible Causes
Blown fuse
Disconnected
harness
Defective harness
Defective Power
PCA
Defective Control
PCA
4.4.10.2 Loss of Up/Down Control from One Foot Switch
Possible Causes
Defective foot
switch
Service Manual
Step Troubleshooting Procedure
Remove observation light transformer bracket on
7.
Power PCA in order to check fuses.
Remove and check fuses F1, F4. Replace as
8.
necessary.
9. Remove Upper Housing.
Check connector and terminals for AC harness at
10.
Power PCA J28.
11. Check in-line connectors and terminals.
Disconnect in-line connectors and check AC
12. voltage on pins 1,3 of E-base harness at top of
West Rail.
Re-connect inline connectors and check AC
13.
voltage at E-base AC inlet connector.
Check E-Base fuse at the AC inlet connector. If OK,
14. then is most likely a foot switch issue (skip to
section 4.4.10.2).
Check the voltage on Power PCA at test point 26
from 2-1 and verify that it is greater than 2V (by
15. probing back of connector). If OK, verify mains
voltage is present at Power PCA connector J28
pins 3-6. If not, replace the defective Power PCA.
While in Service Mode, check the voltage on Power
PCA at test point 26 from 2-1 and verify that it is
greater than 2V (by probing back of connector) to
16. verify that the enable/disable control and listen for
the relay click. If tests fail, check/replace 20 pin
ribbon cable connected to the Power PCA at J23.
Otherwise, replace the Control PCA.
Step Troubleshooting Procedure
Remove E-Base shroud. Verify connectors from the
1. foot switch pedals. If all is OK, replace defective
foot switch.
Chapter 4: Troubleshooting
Troubleshooting Tables
Comments
5.5 mm Hex
Wrench
Needle nose pliers,
Ohm Meter
3 mm Hex Wrench
AC harness part #:
6600-1558-700
E-Base harness
part #:
6600-1562-700
20 pin ribbon
cable part #:
6600-1411-601
Comments
4-41