Programmable Communication Interface Bus System: Operation

Various modules exchange information through a communications port called the PCI Bus. The Powertrain Control Module (PCM) transmits the Malfunction Indicator Light (Check Engine) ON/OFF signal and engine RPM on the PCI Bus. The PCM receives the Air Conditioning select input, transaxle gear position inputs over the PCI Bus. The PCM also receives the air conditioning evaporator temperature signal from the PCI Bus. The following components access or send information on the PCI Bus:

• Instrument Panel
• Body Control Module
• Air Bag System Diagnostic Module
• Full ATC Display Head (If Equipped)
• ABS Module
• Transmission Control Module
• Powertrain Control Module
• Travel Module
• SKIM