Digital signals received by CPU are used to perform all mathematical computations and logic functions necessary to deliver proper air/fuel mixture. CPU also calculates spark timing and idle speed. The CPU commands operation of emission control, "closed loop" fuel control and diagnostic system.
Home/Cadillac/DeVille Concours/Cadillac DeVille Concours (1994-1998)/Repair manual/Theory & Operation/Central Processing Unit (cpu)
Contents
Section: Theory & Operation- Introduction
- Terminology
- Mass Airflow (MAF)
- Speed Density
- Computerized Engine Controls
- Powertrain Control Module (PCM)
- Arithmetic Logic Unit (alu)
- Central Processing Unit (cpu)
- Power Supply
- Memories
- Input Devices
- A/c Request Signal
- A/c Pressure Sensor
- A/c Pressure Switches
- A/c Temperature Sensors
- Battery Voltage
- Brake Switch Feedback
- Camshaft Position Sensor
- Crankshaft Position (ckp) Sensor
- Engine Coolant Temperature (ECT) Sensor
- Fuel Pump Feedback
- Gear Switches
- Ignition/crank Signal
- Intake Air Temperature (IAT) Sensor
- Knock Sensor
- Manifold Absolute Pressure (MAP) Sensor
- Mass Airflow (MAF) Sensor
- Oil Temperature (engine) Sensor (corvette)
- Oxygen Sensor (O2S)
- Park/neutral Position (pnp) Switch
- Power Steering Pressure (psp) Switch
- RPM Reference Signal
- Throttle Position (tp) Sensor
- Throttle Position Switch
- Transmission Range Switch
- Vehicle Speed Sensor (vss)
- Output Signals
- A/c Compressor Clutch
- Canister Purge Control Solenoid
- Computer Controlled Coil Ignition (C(3)I)
- Cooling Fan Relay
- Digital EGR Valve
- Direct Ignition System (dis)
- EGR Control Solenoid
- Electronic Variable Orifice (evo) Actuator
- Fuel Injectors
- Fuel Pump & Fuel Pump Relay
- High Energy Ignition Electronic Spark Timing (hei-Est)
- Hot Light or Coolant Temperature (temp) Light
- Idle Speed Control (isc) Motor
- Linear EGR Valve
- Knock Sensor Operation
- Malfunction Indicator Light (MIL)
- Self-Diagnostics
- Serial Data
- Shift Light
- Shift Solenoids (electronically-Controlled Auto Transmission)
- Torque Converter Clutch
- Fuel Pump
- Fuel Pump Relay
- Fuel Pressure Regulator
- Fuel Control
- Open Loop
- Closed Loop
- Battery Voltage Correction
- Fuel Cut-Off
- Multiport Fuel Injection (mfi)
- Sequential Fuel Injection (sfi)
- Idle Speed
- Ignition System
- Ignition Timing Advance
- Emission Systems
- Exhaust Gas Recirculation (EGR)
- Digital EGR System
- Linear EGR System
- Negative Backpressure EGR Valve
- Evaporative Emission Control
- Carbon Canister
- Canister Purge Control Valve
- Tank Pressure Control Valve
- Except
- Self-Diagnostic System
- "hard Failures"
- "intermittent Failures"
- Miscellaneous Controls
- Electric Cooling Fan
- Electronic Variable Orifice (evo) Actuator (saturn)
- Hot Light or Coolant Temperature Light
- Torque Converter Clutch (non-Electronic Transmission)
- Torque Converter Clutch (electronic Transmission)
- Electronic Transmission
- Abbreviations
- Accessory Drive Belts
- Adjustments
- Airbag
- Anti-Lock/traction Control
- Application
- Automatic HVAC System
- Automatic Trans
- Axle Shafts
- Basic Trouble Shooting
- Body, Cab Control Systems
- Brakes
- Charging System
- Check Lists
- Computer Relearn
- Cooling Fan
- Cruise Control Systems
- Diagnostic Connector Locations
- Door Locks & Anti-Theft Systems
- Drive Cycles
- Driveline/axles
- DTC Index
- Electrical
- Electrical Component Locations
- Electronic Suspension
- Emission Applications
- Engine
- Engine Performance
- Fuses & Circuit Breakers
- Gauges & Instrument Panels
- General Servicing - All Makes
- Headlights
- Heated Glass/defoggers
- Identification
- Manual & Power Steering
- MAP Guidelines
- Mechanical
- Mechanical - Hydraulic
- Metric Conversions
- Mirrors
- Mode 6
- Passive Restraints
- Procedures
- Removal & Installation
- Reset Procedures
- Restraints
- Rpo Codes
- Seats
- Sensor Range Charts
- Specifications
- Starter
- Steering
- Steering Column
- Steering Column Switches
- Sun Roof/t-Top/convertible Top
- Suspension Front
- Suspension Rear
- Testing & Diagnostics
- Theory & Operation
- Traction Control Disable
- Transmission
- Wheel Alignment
- Windows
- Wiper/washer Systems
- Wiring Diagrams - Engine Performance