Lang GCCO-T Service Manual page 54

NO HEAT, COMPUTER MODE
IMPORTANT NOTICE: Before trying to trouble shoot "No Heat in Computer Mode" confirm that the oven heats in
"Manual Mode".
PROBABLE CAUSE
Defective output on CPU
board
ANOMALIES
PROBABLE CAUSE
Display will intermittently
blank out
Intermittently over heats or
under cooks
TROUBLESHOOTING GCCO-PP / -PT CONT'D
CORRECTIVE ACTION
Check for 24VAC at JP2 (while oven is calling for heat).
If no voltage is present:
Board is operating correctly.
If voltage is present:
Replace CPU.
CORRECTIVE ACTION
Check ribbon cable for good connections
Check panel label buttons and confirm that none of the domes are
collapsed.
If domes are collapsed:
Replace panel label.
Check probe for proper resistance.
Check ribbon connection for good connection.
Check probe for good connection.
54