xxiii Gapping Spark Plugs . . . . . . . . . . . . . . . . . . . .588 Installing Spark Plugs. . . . . . . . . . . . . . . . . . . .588 Secondary Wire Service. . . . . . . . . . . . . . . . . .590 Secondary Wire Resistance Test . . . . . . . . . . .591 Replacing Secondary Wires . . . . . . . . . . . . . . .591 Ignition Timing Service . . . . . . . . . . . . . . . . . .592 Measuring Ignition Timing . . . . . . . . . . . . . . . .592 Reprogramming ECM and Ignition Timing . . . .592 Ignition Coil (Coil Pack) Service . . . . . . . . . . .593 Testing Ignition Coil . . . . . . . . . . . . . . . . . . . . .593 Replacing Ignition Coils . . . . . . . . . . . . . . . . . .593 Ignition Switch Service . . . . . . . . . . . . . . . . . .593 Testing Ignition Switch . . . . . . . . . . . . . . . . . . .593 Replacing Ignition Switch . . . . . . . . . . . . . . . . .593 Ignition Control Module Service . . . . . . . . . . .594 Fixed and Variable Dwell . . . . . . . . . . . . . . . . .594 Testing Ignition Control Module . . . . . . . . . . . .594 Heating Ignition Control Module. . . . . . . . . . . .594 Replacing Ignition Control Module . . . . . . . . . .595 Ignition System Sensor Service . . . . . . . . . . .595 Replacing Crankshaft Position Sensor . . . . . . .595 Knock Sensor Service . . . . . . . . . . . . . . . . . . .595 Camshaft Position Sensor Indexing . . . . . . . . .596 Chapter 36 Lights, Instrumentation, Wipers, and Horns—Operation and Service . . . . 603 Light. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .603 Lightbulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . .604 Lighting Systems . . . . . . . . . . . . . . . . . . . . . . .605 Headlamp System . . . . . . . . . . . . . . . . . . . . . .605 Turn Signal, Emergency, and Brake Light Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . .608 Backup Light System . . . . . . . . . . . . . . . . . . . .613 Illuminated Entry System . . . . . . . . . . . . . . . . .613 Light-Monitoring Systems. . . . . . . . . . . . . . . . .613 Light System Service . . . . . . . . . . . . . . . . . . . .613 Lamp Replacement . . . . . . . . . . . . . . . . . . . . .615 No-Light Problems . . . . . . . . . . . . . . . . . . . . . .615 Flickering Light Problems . . . . . . . . . . . . . . . . .616 Light Switch Problems . . . . . . . . . . . . . . . . . . .616 Turn Signal Problems . . . . . . . . . . . . . . . . . . . .616 Brake Light Problem . . . . . . . . . . . . . . . . . . . . .616 Other Light Circuit Problems. . . . . . . . . . . . . . .616 Aiming Headlights . . . . . . . . . . . . . . . . . . . . . .616 Dash Instrumentation. . . . . . . . . . . . . . . . . . . .618 Instrument Cluster . . . . . . . . . . . . . . . . . . . . . .620 Dash Gauges . . . . . . . . . . . . . . . . . . . . . . . . . .620 Digital Instrument Clusters . . . . . . . . . . . . . . . .625 Instrumentation ECM . . . . . . . . . . . . . . . . . . . .625 Instrumentation Power Supply . . . . . . . . . . . . .626 Instrumentation Switches . . . . . . . . . . . . . . . . .627 Dash Monitors . . . . . . . . . . . . . . . . . . . . . . . . .627 Windshield Wipers . . . . . . . . . . . . . . . . . . . . . .627 Windshield Washers. . . . . . . . . . . . . . . . . . . . .629 Rain-Sensing Wiper System. . . . . . . . . . . . . . .629 Windshield Wiper Service. . . . . . . . . . . . . . . . .630 Horns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .631 Horn Service . . . . . . . . . . . . . . . . . . . . . . . . . .631 Chapter 37 Sound Systems and Power Accessories . . . . . . . . . . . . . . . . . . . . . 637 Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .637 Radio System . . . . . . . . . . . . . . . . . . . . . . . . . .638 AM, FM, Digital Radio Systems . . . . . . . . . . . .638 Satellite Radio . . . . . . . . . . . . . . . . . . . . . . . . .639 Auxiliary Audio Input. . . . . . . . . . . . . . . . . . . . .640 Power Booster . . . . . . . . . . . . . . . . . . . . . . . . .640 Antennas . . . . . . . . . . . . . . . . . . . . . . . . . . . . .640 Speakers . . . . . . . . . . . . . . . . . . . . . . . . . . . . .642 CD Players . . . . . . . . . . . . . . . . . . . . . . . . . . . .643 DVD Player. . . . . . . . . . . . . . . . . . . . . . . . . . . .643 Radio Noise . . . . . . . . . . . . . . . . . . . . . . . . . . .644 Power Seats . . . . . . . . . . . . . . . . . . . . . . . . . . .644 Power Seat Service . . . . . . . . . . . . . . . . . . . . .645 Heated Seats . . . . . . . . . . . . . . . . . . . . . . . . . .646 Power Windows. . . . . . . . . . . . . . . . . . . . . . . . .646 Power Window Service. . . . . . . . . . . . . . . . . . .647 Power Door Locks . . . . . . . . . . . . . . . . . . . . . .649 Door Panel Removal. . . . . . . . . . . . . . . . . . . . .649 Power Trunk Release . . . . . . . . . . . . . . . . . . . .649 Power Steering Wheel . . . . . . . . . . . . . . . . . . .650 Rear Window Defogger. . . . . . . . . . . . . . . . . . .650 Window Defogger Service . . . . . . . . . . . . . . . .650 Heated Windshield . . . . . . . . . . . . . . . . . . . . . .652 Reminder System . . . . . . . . . . . . . . . . . . . . . . .652 Cruise Control Systems. . . . . . . . . . . . . . . . . .652 Cruise Control System Service . . . . . . . . . . . .654 Power Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . .655 Driver Information Center . . . . . . . . . . . . . . . .655 Vehicle Degaussing . . . . . . . . . . . . . . . . . . . . .656 Chapter 38 Security and Navigation Systems. . 663 Security Systems . . . . . . . . . . . . . . . . . . . . . . .663 Transponder Key . . . . . . . . . . . . . . . . . . . . . . .664