Troubleshooting and ServiceTeledyne API – Model T300/T300M CO Analyzer
Teledyne Analytical Instruments 259

12.1.4.3. RELAY BOARD STATUS LEDS

There are eight LEDs located on the Relay Board. The most important of which is D1,

which indicates the health of the I2C bus. If D1 is blinking the other faults following

LEDs can be used in conjunction with DIAG menu signal I/O to identify hardware

failures of the relays and switches on the relay (see Section 12.1.3 and Appendix D).

Table 12-4: I2C Status LED Failure Indications
LED FUNCTION FAULT STATUS INDICATED FAILURE(S)
D1
(Red)
I2C bus Health
(Watch Dog
Circuit)
Continuously ON
or
Continuously OFF
Failed/Halted CPU
Faulty Motherboard, Touchscreen or Relay Board
Faulty Connectors/Wiring between Motherboard,
Touchscreen or Relay Board
Failed/Faulty +5 VDC Power Supply (PS1)

STATUS LED’s DC VOLTAGE TEST

POINTS

RELAY PCA PN 04135
Figure 12-5: Relay Board Status LEDs