September 1, 1997
P/N 401789
4 - 23
HUSSM ANN CORPORATION • BRIDGETON, M O 63044-2483 • Printed in USA
Table 4-4 — Troubleshooting—Defrost Board with Mechanical Time Clock
Be sure Board Switch is closed.
Refrigeration Mode
Voltmeter
Voltmeter
Action
Lead Placement
Reading
Lead 1
Lead 2
1
T1 (X1)
T11 (X2)
120
Go to
2
0
Check Power Supply to Board
2
P2,1
T11 (X2)
120
Go to
3
0
Check Fuse F1 (5 Amp) – If OK, Board
Failure
3
P2,2
T11 (X2)
0
End Test
120
Defrost timer contacts closed – Correct
and reset system
Defrost Mode
Voltmeter
Voltmeter
Action
Lead Placement
Reading
Lead 1
Lead 2
1
T1 (X1)
T11 (X2)
120
Go to
2
0
Check Power Supply to Board
2
P2,1
T11 (X2)
120
Go to
3
0
Check Fuse F1 (5 Amp) – If OK, Board
Failure
3
P2,2
T11 (X2)
120
Go to
4
0
Defrost timer circuit open – Check and
correct
4
T4
T11 (X2)
120
Go to
5
0
Board Failure
5
T5
T11 (X2)
120
End Test
0
Board Failure
For each remote component, determine its board terminals from the wiring diagram,
then use standard test procedures.
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