GE PANDA, Service Manual

Page: 89 / 212

Chapter 4: Troubleshooting
Troubleshooting Tables
Service Manual 4-27
4.4.3 Display – LCD and Backlights
4.4.3.1 White Display, Striped Display, or Color Shift
4.4.3.2 Distorted Display: Test or Random Pattern
4.4.3.3 Dim or Non-uniform Light
8.
Using DMM, back-probe J26 pins 1-3 or 2-4.
Depending on dimmer pot setting, voltage range
will be 8 to 12 VAC.
9. If no lamp voltage, replace transformer assembly.
Possible Causes Step Troubleshooting Procedure Comments
Possible Causes Step Troubleshooting Procedure Comments
Poor LCD cable
connection
1. Check LCD cable connection at Control PCA (J1).
LCD Cable PN:
6600-1412-600
2.
If OK, check the LCD cable connection at LCD
module.
3. If OK, replace LCD module.
Possible Causes Step Troubleshooting Procedure Comments
Main application
software not loaded
1. Reload main application code (MAP software).
Possible Causes Step Troubleshooting Procedure Comments
Bad LCD backlight 1.
The backlight may not be connected to the LED
driver board mounted on the Control Board. Check
to make sure connections are mated correctly as
well as any bent pins.
2.
If OK, disconnect the LCD cable at the Control PCA.
Turn on unit and examine for nonuniform lighting.