Service Manual AX300-I
Teledyne Analytical Instruments 40
6 (5) 6
(There is no
indication of
which key is
stuck)
A stuck key has been detected. The second
digit example (5) on the display shows
which key is stuck:
1 - Batt
2 - Cal
5 - Silence
8 - Key Lock
7(2) 7
(There is no
indication of
the type of
DAC failure)
A failure has occurred during the automatic
calibration of the digital to analog converter
(DAC) circuit. The second digit example (2)
shows the type of digital to analog failure.
0 - Measurement
1 - High Test
2 - Low Test
3 - Offset Cal
4 - Gain Cal
Most other problems arise from either mechanical damage from the
instrument falling from a bench or table, or electronic component
failure. In these units, repair or troubleshooting the PCB or individual
component on the board is not feasible. It requires specialized test
equipment and probes not generally available to the public. Under most
circumstances a replacement of the entire PC Board is recommended.
The instrument must be returned to the factory for PCB installation.
Occasionally, depending on the environment of use, keys can
become stuck or function erratically due to contamination. Use a mild
non-abrasive cleaner solution to periodically clean the keypad and
screen. An aerosol jet spray of the type commonly used to clean
computer keyboards can be used to dislodge dirt and accumulations
from the keypad.
The Error Code Table (Table 3-3) includes a description of certain fault
codes, which are diagnostic of some common (usually electronic) problem
with the instrument. Some of these codes refer to specific components on the
PCB that are problematic or have failed. These codes are useful in reporting