Principles of Operation

PRINCIPLES OF OPERATION

The instrument cluster is a hybrid electronic cluster (HEC) that utilizes a microprocessor to control the gauge and indicator functions. Data is sent to the instrument cluster over the high speed controller area network (CAN) bus lines and through hardwired circuitry to individual components such as the oil pressure switch, the parking brake switch and the anti-lock brake system (ABS) module. The instrument cluster acts as a gateway module by receiving information in one format and transmitting it to other modules using another format. For example, the instrument cluster receives the four wheel drive (4WD) data from the 4WD control module over the high speed CAN and sends the 4WD status to the ABS module through hardwired circuitry. This enables communication with modules that are not on the high speed CAN.

When installing a new instrument cluster, it is necessary to upload the module configuration to the scan tool. Following installation of the instrument cluster, download the module configuration from the scan tool into the new instrument cluster. Refer to Information Bus (Module Communications Network) to carry out the programmable module installation (PMI). It is also necessary to carry out a parameter reset procedure whenever a new instrument cluster or powertrain control module (PCM) is installed. Refer to Antitheft and Alarm Systems.

NOTE: The parameter reset procedure must be carried out on passive anti-theft system (PATS) and non-PATS vehicles or a no-start condition may occur.

The following items are configurable:
- Tire pressure monitoring system (TPMS)
- Vehicle type (4x2 or 4x4)
- EPATS configuration status
- PATS

Instrument Cluster Prove-Out

Part 1:

Part 2:

The instrument cluster carries out a display prove-out to verify that all instrument cluster controlled warning/indicator lamps and monitored systems are functioning correctly within the instrument cluster. When the ignition switch is cycled to the ON position with the engine off, the indicators illuminate to prove-out according the table.