Bulb Check General Description

The bulb check function resides in the Body Function Controller (BFC). Every time the Ignition Switch transitions from ACC to RUN, an Instrument Cluster bulb check will occur for a calibrated amount of time for specified indicators. Bulb check will override the OFF state of the affected indicators. The Body Function Controller (BFC) will determine which indicators to bulb check by looking at an EEPROM table. Every Serial Peripheral Interface (SPI) indicator has a bit in the EEPROM table. The gauges will WOW during a bulb check. A WOW is when all of the gauge indicators are moved at the same time and all indicators are lit. If there is an indicator lit before the WOW, the indicator shall remain lit after this function has concluded.