TB 9-4931-538-40
b. Remove HORIZ. CONTROL BOARD A3 (fig. 9) as necessary to perform c and d below.
c. Using four-wire resistance measurement technique, connect multimeter negative
leads to A3TP3 and positive leads to A3TP2 (fig. 9).
d. Measure and record the dc resistance value in ohms of A3R46 (fig. 9) in l and n
below. (Two places after the decimal are required. Example: 200.06 ).
e. Reinstall HORIZ. CONTROL BOARD A3 (fig. 9).
f. Disconnect ribbon cables from A3Jl of HORIZ. CONTROL BOARD A3 (fig. 9) and
A4Jl of ADC BOARD A4 (fig. 10) (rear of chassis).
Figure 9. Top rear corner of horizontal control board A3 and top view of mainframe card cage.
Figure 10. Top rear corner of ADC board A4 and top view of mainframe card cage.
g. Remove multimeter four-wire measurement technique connections and connect
negative leads to A3TP3 and positive leads to A3TP2 on HORIZ. CONTROL BOARD A3 (fig. 9).
h. Connect a short to A3TP1 and A3TP2 on HORIZ. CONTROL BOARD A3 (fig. 9).
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