No Bus Indicator

The no bus indicator is serviced as a unit with the odometer vacuum fluorescent display unit in the instrument cluster.

The no bus indicator gives an indication to the vehicle operator when the electronic communication data bus is ineffective. This indicator is controlled by the instrument cluster logic circuit based upon cluster programming and electronic messages not being received over the controller area network data bus.

The no bus indicator function of the odometer VFD unit is completely controlled by the instrument cluster logic circuit. This logic only allows the indicator to operate when the instrument cluster receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the odometer VFD no bus indicator is always off when the ignition switch is in any position except ON or START. The instrument cluster turns ON the no bus indicator for the following reasons:

• >>No Electronic Communication Messages<< - Each time the ignition switch is turned to the ON position and the cluster does not receive electronic communication messages over the CAN data bus, the no bus indicator illuminates. The indicator remains illuminated until CAN bus communication is restored or until the ignition switch turns to the OFF position, whichever occurs first.

The instrument cluster continually monitors the CAN data bus to determine the status of many sensors and systems throughout the vehicle. If bus communication is interrupted, the cabin compartment node cannot provide accurate displays and outputs.

Use a diagnostic scan tool for proper diagnosis of the no bus indicator, the CCN, the CAN data bus or the electronic communication. Refer to the appropriate diagnostic information.