C
HAPTER
3. M
AINTENANCE
P
ROCEDURES
3-113
02.9631.0010
CONFIDENTIAL
15 Jan 98
3.3.19 Thumbwheel Switch Assembly Removal and
Replacement
Parts:
1 EA
CABLE ASSY, THUMBWHEEL SWITCH (25.7020.0001)
Tools:
Screwdriver, Phillips #1
Screwdriver, Phillips #2
Pin removal tool
To remove and replace thumbwheel switch assembly (Figure 3-39):
HOUR METER
THUMBWHEEL SWITCH
THUMBWHEEL
NOTE ROUTING OF
20 POSITION THUMBWHEEL
SWITCH CONNECTOR (REMOVE
LVS TO ACCESS CONNECTOR)
THWHLEXP
CABLE ASSEMBLY
THUMBWHEEL SWITCH CABLE
Figure 3-39. Thumbwheel Switch Removal and Replacement
Step 1.
Remove power to luminaire.
Step 2.
Open chassis lid.
a. At electronics chassis, remove six 10-32x3/8"PPB screws
that secure chassis lid to chassis and open lid.
Step 3.
Remove low voltage supply board.
a. At card cage assembly, carefully pull and slide out low
voltage supply board.
Step 4.
At motherboard, disconnect 20-position thumbwheel switch
connector.