Teledyne API – Model T300/T300M CO Analyzer Troubleshooting and Service
263
12.1.4. STATUS LEDS
Several color-coded light-emitting diodes (LEDs) are located inside the instrument to
assist in determining if the analyzer’s CPU, I
2
C bus and relay board, GFC Wheel and the
sync/demodulator board are functioning properly.
12.1.4.1. MOTHERBOARD STATUS INDICATOR (WATCHDOG)
DS5, a red LED, that is lo
cated on upper portion of the motherboard, just to the right of
the CPU board, flashes when the CPU is running the main program loop. After power-
up, approximately 30 to 60 seconds, DS5 should flash on and off. If characters are
written to the front panel display but DS5 does not flash then the program files have
become corrupted. If after 30 – 60 seconds neither the DS5 is flashing or no characters
have been written to the front panel display then the CPU is bad and must be replaced.
Motherboard
CPU Status LED
Figure 12-3: CPU Status Indicator
06864B DCN6314