Maintenance Indicator - Operation

OPERATION

The ASSYST maintenance indicator gives an indication to the vehicle operator as to when certain maintenance operations should be performed. This indicator is controlled by a microprocessor on the instrument cluster circuit board based upon cluster programming, time data taken from the electronic digital clock integral to the cluster, as well as vehicle distance, coolant temperature, engine oil temperature, engine oil level, engine oil quality, engine speed, and engine load data.

Using all of the available data and internal programming, the ASSYST microprocessor then calculates the estimated time and distance to the next required maintenance interval. Besides the internal clock and programming, the cluster relies upon electronic messages received over the Controller Area Network (CAN) data bus from the Controller Antilock Brake (CAB) (also known as the Antilock Brake System/ABS or Electronic Stability Program/ESP controller), as well as those received from the Engine Control Module (ECM) and the Body Control Module (BCM) (also known as the Signal Acquisition and Actuation Module/SAM).

The ASSYST microprocessor uses the multi-function indicator to display visual reminders and, when necessary, issues audible alerts to the vehicle operator through the audible tone transducer on the cluster circuit board. See the owner's information packet in the vehicle glove box for more information on the recommended vehicle maintenance requirements as well as the features, use, operation and resetting procedures for the ASSYST maintenance indicator.

For proper diagnosis of the ASSYST maintenance indicator, the BCM, the CAB, the ECM, the ElectroMechanical Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN or KOMBI), the CAN data bus or the electronic communication related to ASSYST maintenance indicator operation, a diagnostic scan tool is required. Refer to the appropriate diagnostic information.