Troubleshooting
Touch Screen Is Defective
17
Touch Screen Is Defective
Acknowledge Switch is Defective
Table 9. Troubleshooting Procedure for Defective Touch Screen
Probable Cause
Action
OK?
Action
1. Bad Display
cable, loose dis
-
play cable.
1. Reseat display cable.
No
Replace SD card. If chang
-
ing SD card does not fix
problem, replace Display/
CPU assembly.
Table 10. Troubleshooting Procedure for Defective Acknowledge (Ack) Switch
Probable Cause
Action
OK?
Action
OK?
Action
1. The Ack cable
plug is loose or
not plugged in
Ack connector.
Verify cable is not loose.
No
Reseat cable connector.
Yes
Go to next cause.
2. Ack cable is bro
-
ken.
Verify cable is not broken.
Yes
Replace the Ack/CPU
assembly.
No
Go to next cause.
3. Ack cable con
-
nector incor
-
rectly installed.
Verify all pins of Ack cable plug are seated in
the Ack switch connector, J40.
Legend:
1. Connector J40 on CPU board. Notice the
cable plug is over all five pins of the connec
-
tor.
2. Ack cable is attached to the metal shield.
3. Metal shield. Notice the orientation of the
shield, Ack cable underneath.
No
Reconnect Ack plug.
Yes
Replace SD Card
No
Replace Ack/CPU
assembly.
2
1
3
