Light path diagnostic LEDs are a system of LEDs on the alarm panel of the JCS1200 platform and the JCS1200 components that can be used to diagnose system errors. If the front or rear system-error LED on the JCS1200 platform is lit, one or more error LEDs on the JCS1200 components also might be lit. These LEDs help to identify the cause of the problem.
The following example shows how to use the LEDs to diagnose a system error: