Test Description

The number below refers to the step number on the diagnostic table.

1. 2. Lack of communication may be due to a partial malfunction of the serial peripheral interface (SPI) circuit or due to a total malfunction of the serial peripheral interface (SPI) circuit of the instrument panel cluster (IPC).
2. 4. The presence of DTCs which begin with "U" indicate some other module is not communicating on the class 2 serial data circuit. The specified procedure will compile all the available information before tests are performed.
3. 5. The presence of DTCs U2000-U2007 indicate a malfunction in the serial peripheral interface (SPI) between the IPC and the BCM.
   Fig 1: Diagnostic System Check - Instrument Cluster Diagnostic Procedure

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