Service Manual

14
The diagnostic procedure is a sequence check that allows you to diagnose the electrical
system and components. Before proceeding, check for correct installation and proper
voltage per nameplate.
See the table for default cabinet temperature control settings.
Model Default Cabinet Temperature
Control Setting
Approximate Default Temperature
Undercounter
Worktop
Between 4 and 5 Refrigerator: 34°F (1°C)
Freezer: -5°F (-21°C)
Prep Table Between 4 and 5 34°F (1°C)
The diagnostic procedure is a sequence check that allows you to diagnose the electrical
system and components. Before proceeding, check for correct installation and proper
voltage per nameplate.
Conrm that the appliance location meets factory requirements:
• This appliance is not intended for outdoor use. Normal operating ambient
temperature should be within 45°F to 86°F (7°C to 30°C).
• The appliance should not be located next to ovens, grills, or other high heat
producing equipment. Check CM using the steps in "II.C. Control Module Check."
Note: • When checking voltage (115VAC), always choose a neutral white (W) wire to
establish a good neutral connection.
• CM has high and low voltage protection. If off on either protection, no LED is
visible and all components are off.
High Voltage: 135VAC
Low Voltage: 90VAC
• Solid red LED for 5 sec. at startup.
• Flashing green LED: Normal operation.
• Flashing red LED: check cabinet thermistor and defrost thermistor (if applicable).
• CM has a 2 min. minimum on time and 2 min. minimum off time for Comp.
1) Unplug the appliance from the electrical outlet.
2) Remove the rear panel.
3) Plug the appliance back into the electrical outlet. If appliance was in defrost when power
supply was disconnected, defrost is terminated and normal cooling cycle begins when
power supply is reconnected.
4) Startup/Cool Down–There is a slight delay (solid red LED for 5 sec., then ashing
green LED). Temperature above setpoint at CTh and if applicable, conrm appliance is
not in a defrost cycle (PT and Freezers). Comp, CondFM, and EvapFM energize. 2-min.
Comp on timer starts.
Freezers: PH, and MH energize.
a) CTh Diagnosis: If CTh fails, a red LED ashes along with the green LED on the CM.
Conrm CTh is properly connected to CM. Check Ohm reading of CTh. Replace as
needed.
b) TD Diagnosis: Conrm TD is set between 4 and 5. Check Ohm reading of TD.
Replace as needed.