C.
Bar Controller.
1.
Disassemble the Premium Vision
lightbar as described in the Service and Maintenance
section of the Premium Vision Hardware Installation
and Maintenance Instructions (Part No. 255274).
2.
Locate the bar control circuit board.
3.
Remove the screws which retain the
circuit board.
4.
Disconnect the modular connector.
Carefully lift the circuit board just enough to discon-
nect the 14-pin connector (J9) which connects the bar
control circuit board to the lamp driver circuit board.
The microprocessor IC should now be accessible.
5.
Gently pry the microprocessor (IC10)
out of its socket with a small screwdriver.
6.
See figure 3-4. Insert the new micro-
processor IC (“BC” in the part number) in the empty
socket. Ensure that the notch on the new micropro
3-2
3.
See figure 3-2. Insert the new micro-
processor IC (“RB” in the part number) in the empty
socket. Ensure that the notch on the new micropro-
cessor IC is facing the same direction as the old one
(toward F1—20-ampere fuse) and that all IC pins are
properly inserted in the socket—not bent under.
4.
Remove the relay circuit board as
described in the Premium Vision Hardware Installa-
tion and Maintenance Instructions.
5.
Gently pry the amplifier circuit board
microprocessor (IC2) out of its socket with a small
screwdriver.
6.
See figure 3-3. Insert the new micro-
processor IC (“AB” in the part number) in the empty
socket. Ensure that the notch on the new micropro-
cessor IC is facing the same direction as the old one
(toward the circuit board mounted transformer—T1)
and that all IC pins are properly inserted in the
socket—not bent under.
7.
Reassemble the Amplifier/Relay Unit.
Figure 3-2. Relay Circuit Board Microprocessor.
Figure 3-3. Amplifier Circuit Board Microprocessor.
