Service Manual

15
1. Refrigerator
5) Startup/Cool Down–MH and PH energize. There is a slight delay, Comp, ConFM, and
EvapFM energize. Cabinet temperature appears on display and 2-hr. defrost timer
starts. Note, if DTh is above 50°F (10°C) EvapFM is de-energized.
a) MH Diagnosis: MH energizes at startup. If 115VAC is present, check amp draw of
MH. If an amp reading is not present, check the continuity of MH. If defective, replace
MH.
b) EvapFMDiagnosis: Conrm that EvapFM(s) energize. If not, conrm DTh is at 50°F
(10°C) or lower, doors are closed and DS engaged, check DS continuity.
If DTh is above 50°F (10°C), wait for evaporator to cool down. If DS is engaged and
contacts are open, replace DS. If DS is engaged and contacts are closed, check for
115VAC at CM 5 (F) dark blue (DBU) wire to neutral white (W) wire. If 115VAC is not
present, replace CM. If 115VAC is present, check EvapFM blades for binding and
EvapFM continuity.
c) Solid Door Cabinet Light Diagnosis: LED(s) are activated from door switch. Open
the door (upper on HS/HG), conrm LED(s) energizes. If not, with door open, check
for 5 to 12VDC at CM S4 brown (BR) to CM S4 blue (BU). If 5 to 12VDC is not
present at CM S4 brown (BR) to CM S4 blue (BU), conrm 115VAC power supply
to CM at terminals 2 (L) black (BK) to 3 (N) white (W). If 115VAC is present, and
LED(s) are off, check DS continuity. If DS is disengaged (open) and contacts are
closed, replace DS. IfDS is disengaged (open) and contacts are open, check for
115VAC from CM 6 (LED) (Y) to a neutral (W). If 115VAC is not present, replace CM.
If 115VAC is present at CM 6 (LED) (Y) to a neutral (W) and LED(s) are not on, check
for 24VDC at DCD black (BK) wire to DCD red (R) wire. If 24VDC is not present,
check continuity of DCD driver. If open, replace DCD driver. If 24VDC is present
and LED(s) are not on, check wiring harness and wiring connections from DCD to
LED(s). Ifconnections are good and LED(s) are not on, replace LED(s).
d) Glass Door Cabinet Light Diagnosis: LED(s) are activated from control module
light switch. Glass door models feature lights that are controlled by the Standby/Light
control button located on the control module. Press the standby/light button quickly
to turn the light on or off. If LED(s) fail to turn on, check for 115VAC from CM 6 (LED)
(Y) to a neutral (W). If 115VAC is not present at CM 6 (LED) (Y)to a neutral (W),
replace CM. If 115VAC is present at CM 6 (LED) (Y) to a neutral (W) and LED(s) are
not on, check for 24VDC at DCD black (BK) wire to DCD red (R) wire. If 24VDC is
not present, check continuity of DCD driver. If open, replace DCD driver. If 24VDC is
present and LED(s) are not on, check wiring harness and wiring connections from
DCD to LED(s). Ifconnections are good and LED(s) are not on, replace LED(s).
e) CM Diagnosis: Cabinet temperature appears on display. If not, check for 115VACat
CM 2 (L) (BK) to CM 3 (N) (W). If 115VAC is not present, check power cord
connections and breaker/fuse. Conrm wiring connections are secure for both
CM 2 (L) (BK) (power supply) and CM 3 (N) (W). If 115VAC is present and display is
off, replace CM.