OHAUS TROOPER, Service Manual

Page: 22 / 70

2-10
CHAPTER 2 DIAGNOSIS
SYMPTOM
Scale will not turn on with
new batteries installed.
PROBABLE CAUSE
Incorrect battery installation.
Wiring harness defective or
battery clips connection bro-
ken.
Membrane switch defective.
Main PC Board is defective.
REMEDY
Check position of batteries.
Remove the 6 screws from the bottom
cover of the scale, carefully remove the
platform, top cover and remove the flex-
ible cable from the Main PC board.
Check dc voltage at pins 1 and 3 of
connector J7 on the Main PC board. See
Figure 2-3. Voltage should read approxi-
mately 9 Volts dc. If voltage is not present
at the connector, remove the batteries and
make a continuity test between each of
the connectors in the battery box to con-
nector J7, pins 1 and 3 on the Main PC
board. Resistance should be 0 ohms for
the red lead and 0 ohms for the black
lead. If an open condition exists, trace
wiring and resolder or replace wiring as
necessary. If OK, proceed.
See Table 2-10.
If the scale fails to turn on with a new
membrane switch, the Main PC board is
defective and should be replaced.
-> Repair Procedures 3.5.
TABLE 2-9 TROOPER COUNT SCALE - WILL NOT TURN ON USING BATTERIES.