XP3210-006 – 18JUL97
7
[4] Locate the DC-DC CONVERTER.
Important
There are 2 styles of DC-DC CONVERTER. You can
replace the DC-DC CONVERTER only if it is the same
style as the DC-DC CONVERTER replacement, Part
Number 981821, in the KEYPAD Repair Kit.
[5] Compare the DC-DC CONVERTER on the
CIRCUIT BOARD to the replacement DC-DC
CONVERTER in the Repair Kit.
[6] If the DC-DC CONVERTER on the CIRCUIT
BOARD is the same style as the replacement part,
advance to Step 7.
If the DC-DC CONVERTER is not the same style
as the replacement part, you must replace the
KEYPAD OVERLAY/CIRCUIT BOARD
ASSEMBLY. Advance to the procedure
Replacing the KEYPAD OVERLAY/
CIRCUIT BOARD ASSEMBLY on page 13.
[7] Use the following table to help you measure the
input and output voltages of the DC-DC
CONVERTER. The KEYPAD must be energized
to check the voltage.
Caution
Be careful not to cause a short circuit between any of
the pins on the DC-DC CONVERTER.
[8] If the input and output voltages are correct,
advance to the procedure Replacing the
KEYPAD OVERLAY/BOARD ASSEMBLY
on page 13.
[9] If either voltage is not correct, continue with the
next step.
Voltmeter Connections
Red
Black
(ground)
Requirement (VDC)
Pin 1
C36
> +7.0 Volts (Input)
Pin 3
C36
5.0 +/- 0.1 Volts (Output)
H027_2528AC
H027_2528ACA
BOARD AY
DC-DC CONVERTER
KEYPAD
OVERLAY/
H027_2518AC
CONVERTER
DC-DC
GROUND LEAD
METER
VOLT-OHM
C36 CAPACITOR
PIN 3
PIN 2
PIN 1
H027_2518ACA