1. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Chapter 20 Lighting Systems

2. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Lighting Systems Provides interior and exterior illumination Some lighting is regulated by federal laws Automotive bulbs are electrically operated

3. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Incandescent Lamps A lamp generates heat and light as current flows through the filament Filament vacuum sealed in glass envelope Lamps are normally single filament or double filament

4. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.

5. Headlights Have become integral part of vehicle styling Must have low and high beam lights

6. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Sealed-Beam Headlights An air-tight light and reflector assembly May contain low, high, or both headlight filaments Made obsolete by halogen bulbs and composite light assemblies

7. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Halogen Lamps Halogen identifies a group of nonmetallic elements, including chlorine, fluorine, and iodine Most halogen lamps filled with iodine vapor Tungsten filament can withstand higher temperature because of the halogen

8. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Composite Headlights Use a replaceable bulb Improves aerodynamics, fuel economy, and vehicle styling

9. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Cylindrical Housings Many headlights have cylindrical bulb housings Enables the light beam to be projected without much scattering

10. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. HID Headlights Also called xenon headlamps Use gas-discharge lamps Electronically controlled Use an electric arc instead of a filament Use high-voltage to jump gap and about 80 volts to maintain

11. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Halogen Compared to Xenon

12. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Bi-Xenon Lights Some vehicles use xenon lamps for high and low beams Use an additional halogen lamp for flash- to-pass

13. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. LED benefits: – Do not require vacuum or high voltage – Use up to 40% less power – Provide whiter light than xenon – Environmentally friendly – Longer operating life – More shock resistant – Reduce glare perception – Smaller size which provides more flexibility LED Headlights

14. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. LED Headlights (Cont.)

15. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Daytime Running Lights (DRLs) Added safety feature Headlights connected in series when the ignition switch is on and headlights are off When headlights are turned on normal operation returns

16. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Auxiliary Lights Fog lights are common auxiliary lights Mounted low to cut under fog Normally turned off if high-beams are on

17. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Knowledge Check Technician A says LED headlights require high- voltage to operate. Technician B says HID headlights use a special high-voltage filament to generate a brighter light. Who is correct?

18. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Controls most exterior lighting Instrument panel (IP) lights come on when switch is in park or headlight position IP light brightness may be controlled by rheostat in headlight switch The system can be power-side or ground- side controlled Headlight Switches

19. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Headlight Switches (Cont.)

20. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Allows driver to switch between high- and low-beams Connected in series with headlight circuit Typical dimmer switch Dimmer Switches

21. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Most steering-column-mounted dimmer switches have flash-to-pass Illuminates the high-beams even with headlights off Completes a circuit to the high-beam headlights Flash-to-Pass

22. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Light-sensitive, automatic, on-off control Uses a photocell sensor/amplifier Manual headlight switch operation overrides automatic setting High-beam detection system turn high- beams on and off – Forward looking light sensor detects conditions Automatic Light Systems

23. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Automatic Headlight Switch

24. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Adaptive Headlights Inputs from steering system and vehicle speed Aims headlights in direction of turning One design uses motors to position headlights Second design uses extra turning lamps Adaptive system may use GPS data

25. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Headlamp failures are usually caused by burned out bulbs Check for voltage at the bulb before replacing it If more than one lamp is not working, carefully check the circuit If the voltage regulator is defective, the high voltage will cause lamps to burn out prematurely Headlamp Service

26. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Restoring Headlight Lenses Over time the polycarbonate deteriorates, clouding the lens Polishing may restore the lens

27. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Headlight Replacement Sealed beam lights are secured with a clip or retaining ring Accessing the light may require removing bumper covers or inner fender liners Do not touch the glass

28. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. HID Diagnosis and Service Turning headlight switch on powers the HID transformer Bi-xenon system uses a shutter to redirect light A delay before full illumination is normal Blue to white light is normal

29. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. HID Bulb Replacement HID bulbs do not suddenly stop working As bulb wears it will shut off and turn on Will become more frequent Increases wear on the transformer If lights are flickering, the transformer should be replaced with the bulbs

30. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. HID Transformer

31. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Headlight Adjustment Before adjusting headlights: – Vehicle must be on a level floor – Remove ice, snow, or mud – Try to adjust with fuel tank half full – Check vehicle ride height – Inflate tires to specifications – Wheel alignment should be correct – Settle the suspension before adjustment

32. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Headlight Adjustment (Cont.) Many vehicles have built-in bubble levels for headlight adjustment Headlight aiming equipment uses a split mirror system and levels for adjustment If neither are available, a screen can be used to determine headlight accuracy

33. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Headlight Adjustment (Cont.)

34. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.

35. Auto-Leveling Headlights Found on xenon equipped vehicles Keeps headlight aim within a certain range regardless of load and driving conditions Each headlight has a leveling motor Uses input from front and rear suspension Diagnosed with a scan tool

36. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Knowledge Check What type of tools and equipment may be necessary to adjust headlight aim?

37. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Automatic Headlight System Diagnosis Inspect for any obstruction of the photo cell Proper photo cell alignment is necessary Follow the manufacturer’s testing procedures

38. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Adaptive Headlight Diagnosis Controlled by a headlamp control module Monitor inputs with a scan tool – Data used from ECM, TCM, EBCM, and BCM Headlamp module calculates desired angle Module can also monitor motor control circuits

39. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Bulbs are quickly checked with ohmmeter or powered test light Inspect for corroded or loose wiring Many exterior lights are exposed to climate and weather conditions that can damage wiring and sockets Basic Lighting System Diagnosis

40. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Checking Bulb Resistance

41. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Scan Tool Diagnostics

42. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Other Light Bulbs Most designs prevent using incorrect bulb type May be several types within the design Bulbs have trade numbers

43. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.

44. Bulb Replacement Make sure the replacement is the correct bulb Inspect the bulb socket Often removal of light assembly is necessary Do not remove lenses from light assemblies

45. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Bulb Replacement (Cont.) Gain access the bulb Remove the bulb and inspect the socket Replace with the correct bulb

46. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Light Circuits Single filament bulbs use two wires Double filament bulbs will have two hot wires and a ground Light circuits can be either power or ground controlled

47. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Rear Exterior Lights Rear lights include – Brake lights – Taillights – Turn signal / hazard lights – Back-up lights

48. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Each system has a switch to control operation Turn signals only powered with key on Stop and hazard lights powered with key off Turn signal and hazard lights may be part of multifunction switch Turn, Stop, and Hazard Warning Lights

49. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Flashers Used by turn signal and hazard systems Older vehicles use temperature sensitive bi-metallic strip

50. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Electronic Flasher Modern flashers are electronic An inoperative turn signal bulb generally causes a different flashing rate

51. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Controlled by brake light switch normally mounted on brake pedal bracket All late model vehicles have a center high- mounted stop light (CHMSL) Brake light switch input is also used for cruise control, ABS, and traction control systems Brake (Stop) Lights

52. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Adaptive Brake Lights Can operate under standard illumination during normal braking Under intense braking or ABS intervention, additional lights are lit Increases the size of brake lights

53. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Brake Light Switches

54. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Brake Light Circuit

55. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. LED Lights LED and neon lights used for some brake, tail, and turn signal lights LED illuminate faster, consume less power, and last longer than incandescent lights

56. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Back-Up Lights Activated by the park- neutral switch on automatic transmissions Manual transmission have separate reverse light switch

57. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Knowledge Check Technician A says a burned out bulb can cause the turn signals to not blink properly. Technician B says installing an incorrect bulb may cause the turn signals to not blink correctly. Who is correct?

58. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Interior Light Assemblies Engine compartment light Glove box light Luggage compartment light Trunk lid light Vanity light

59. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Courtesy Lights Provides light inside the vehicle Operated by doors, headlight switch, or separate switch Often tied into keyless entry and/or alarm Map lights usually independent of courtesy lights

60. © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Illuminated Entry System Illuminated lock cylinders Most have an electronic actuator module Activated by lifting outside door handle or keyless entry