xiii Starter Motor Construction .......................................... 366 Starter Drive System ....................................................... 366 Starter Solenoid ................................................................ 369 Starter Actuating Switches ........................................... 372 Chapter 18 Chassis Electrical . . . . . . . . . . . . .377 Chassis Wiring .................................................................. 377 Wire Sizes ........................................................................... 377 Wiring Harness ................................................................. 377 Fiber-Optic Cables ........................................................... 378 Circuits ................................................................................ 379 Circuit Protection Devices ....................................... 381 Fuses .................................................................................... 381 Circuit Breaker .................................................................. 382 Fusible Link ........................................................................ 383 Chassis Computer Functions .................................. 383 Vehicle Lights and Light Switches ....................... 384 Headlights .......................................................................... 384 Stoplights and Switches ................................................. 386 Turn Signals and Switches ............................................ 386 Backup Lights and Switches ......................................... 387 Instrument Panel Lights ................................................ 387 Convenience Lights ......................................................... 388 Chassis-Mounted Solenoids and Relays .......... 388 Motor Control Relays ...................................................... 388 Trunk Release Solenoids ................................................ 389 Power Door Lock Solenoids and Switches ............... 389 Horns and Horn Relays ............................................... 391 Horn Relay .......................................................................... 391 Rear Window and Mirror Defrosters ................. 392 Heated Seats ...................................................................... 392 Chassis-Mounted Motors .......................................... 392 Chassis X-By-Wire Systems ........................................... 392 Windshield Wiper Motors and Controls ................... 393 Power Door Lock Motors ............................................... 393 Power Window, Tailgate, Sliding Door, and Sunroof Motors .............................. 393 Convertible Top Motors and Switches ....................... 393 Electric Gauges................................................................. 393 Cruise Control ................................................................... 394 Vehicle Speed Sensor ...................................................... 394 Operator Controls and Control Module .................... 394 Throttle Actuator ............................................................. 394 Adaptive Cruise Control ................................................ 394 Keyless Entry and Security Systems ................... 394 Remote Start Systems ..................................................... 396 Air Bag Systems ................................................................ 397 Diagnostic Control Module ........................................... 397 Impact Sensors ................................................................. 397 Coil Assembly and Inflator Module ............................ 398 Air Bag Operation ............................................................ 398 Side Air Bags ...................................................................... 398 Chassis Electronic Devices ....................................... 399 Active Safety Systems ................................................... 399 Active Safety System Operation ................................... 400 Chapter 19 Engine Clutches . . . . . . . . . . . . . 405 Clutch Purpose ................................................................. 405 Clutch Construction ..................................................... 405 Flywheel .............................................................................. 405 Clutch Disc ......................................................................... 406 Pressure Plate Assembly ................................................ 408 Clutch Release Lever Operating Mechanism ........... 412 Clutch Housing and Input Shaft (Clutch Shaft) ...... 412 Complete Assembly ......................................................... 413 Other Types of Clutches ................................................. 413 Dual Clutches .................................................................... 413 Clutch Operation ............................................................ 414 Clutch Pedal Linkage .................................................... 414 Mechanical Linkage ........................................................ 415 Hydraulic Linkage ............................................................ 415 Self-Adjusting Clutch ...................................................... 416 Clutch Pedal Free Travel ................................................ 417 Clutch Cooling .................................................................. 417 Riding the Clutch ............................................................. 417 Will a Clutch Explode? ................................................... 417 Chapter 20 Manual Transmissions and Transaxles . . . . . . . . . . . . . . .421 Manual Transmissions and Transaxles .................................................................. 421 The Engine Needs Help ............................................... 421 How Is Torque Multiplied? ............................................ 421 Torque Multiplication through Gears ........................ 422 Transmission Cases ......................................................... 424 Transmission Construction .......................................... 424 Synchronizing Mechanism ............................................ 425 Transmission Operation ................................................ 427 Power Flow through a Simple Transmission ........... 428 Five-Speed Transmission Power Flow ....................... 429