144 Part Number: 000015431 Rev01 5/19
Ice Thickness Probe Diagnostics
1. Perform Control Board Self Check and insure the
internal ITP circuit passes before proceeding.
(Menu/Service/Diagnostics/Control Board/Self Check)
• Ice Thickness Circuit: Pass = Continue with step #2.
• Ice Thickness Circuit: Fail = Change control board.
2. Remove all ice from the evaporator when present, by
initiating a manual harvest in the service menu.
3. Press the power button and turn off the ice machine.
4. Disconnect power to the ice machine at the main
disconnect.
5. Inspect the ice thickness probe for physical damage.
On the face of the probe look for bulging, cracks
around the nipple and deformed pivot pins or pivot
pin arms.
6. Verify the ice thickness probe gap is approximately
9/32" (7 mm) and the ice thickness probe wire and
bracket do not restrict movement of the probe. See
“Ice Thickness Probe (Initiates Harvest)” on page
142.
7. Reapply power to the ice machine at the main
disconnect and confirm the ice machine is off.
8. Navigate to Real Time data (Menu/Service/Data/
Real Time data/Inputs) and observe ITP FFT 100 Hz &
9. Observe the initial number range and perform a tap
test.
• Remove the water curtain or splash shield if present.
• Lift the ice thickness probe and carefully tap the nipple
on the face of the probe for at least 10 seconds.
NOTE: When performing tap test:
• Pass = ITP is not the problem
• Fail = Check DC Voltage on the control board