Identify causes of brighter than normal, intermittent, dim, or no headlight and daytime running light (DRL) operation.

Lesson Plan for

DIT 190-191

ELECTRICAL/ELECTRONIC SYSTEMS

Course HS Title: / Electrical/Electronic Systems / Program:
KCTCS Courses included in HS Title: (Lesson is prepared for course highlighted.)
KCTCS Course No. / KCTCS Course Title
DIT 190 / Electrical/Electronic Systems
Introduction/Context / This lesson will instruct the student on how to identify causes of brighter than normal, intermittent, dim, or no headlight and daytime running light (DRL) operation. Knowledge of these techniques and the skills required to correct problems associated with this task are necessary for a student to acquire if they wish to compete for high paying, high skilled jobs in a Diesel Repair Facility. Entry level technicians need to be able to perform this task to 100% accuracy. Incorrectly performing this task can lead to an accident or create customer satisfaction issues.
Prepared By / School / Date:
Grade Level / No. Students / No.IEP's: / Lesson Length:
Task
Identify causes of brighter than normal, intermittent, dim, or no headlight and daytime running light (DRL) operation.
Objective
Given the proper tools and instruction, the student will be able to identify causes of brighter than normal, intermittent, dim, or no headlight and daytime running light (DRL) operation, and pass a written test covering the task with 100% accuracy.

Connections:

Skills Standards:
OH 001
OH 002
OH 003
OD 002
OD 003
OD 005
New Common Core Standards:
RST 11-12 3
A-CED-4
N-Q.1
Common Core Technical Standards:
TD-OPS 2
TD-SYS 2
New Generation Science Standards:
HS-PS2-5.
HS-PS3-3.
HS-PS3-5.

INSTRUCTIONAL MATERIALS/TECHNOLOGY

Teacher Designed Materials and Other Handouts


Textbooks and Workbooks

Author / Title/ISBN No. / Edition / Publisher / Pages
Various / Electrical/Electronic System ASE Test Prep T6 / Fifth / Delmar / 27-28


Equipment

Quantity / Item / Source


Content/Presentation/Demonstration Outline

Explain to students that an alternator that is overcharging is the only cause for multiple lights that are brighter than normal. They can verify this by checking alternator output with a DMM. A malfunctioning charging system can also cause dim light operation if chassis voltage is too low. Tell them they can verify this problem with a DMM, also.
Inform students that dim lights can also be caused by problems such as excessive resistance in fuse holders, relays, wiring, switches, connectors, and chassis grounds. Of all the aforementioned possibilities, tell them to suspect the chassis grounds first. Explain that poor grounds cause the majority of problems related to this complaint, from simple loose hardware to poor metal-to-metal contact between chassis components. Let them know that voltage drop tests between the ground side of the bulb and’ the battery negative post will confirm ground integrity problems.
Tell students that intermittent operation can be caused by a cycling circuit breaker or a loose connection somewhere in the circuit. Circuit breakers are often incorporated directly into the headlight switch. Inform them that a cycling circuit breaker is caused by either a defective breaker or an overload in the system, and will result in on-off circuit operation. Loose connections are harder to find. Tell them that a good tip would be to gently pull and wiggle suspect harnesses and connectors while watching the light action.
Instruct students that a blown fuse, defective circuit breaker, bad switch, or an open in the wiring generally causes no light operation. At this point, tell them it is best to get a wiring diagram for the vehicle and probe with a test light at various points downstream from the power source until you find the open.
Let students know that daylight running lights (DRL) are now mandated in some jurisdictions in the United States and in all of Canada. Some OEMs specify DRLs as a default option and fleets are using them increasingly. Explain that DRLs are a safety feature and illuminate anytime the vehicle is running and the vehicle headlights are not switched on. The DRL circuit is illuminated at key-on when the vehicle is in gear.
Tell students that the following are some symptoms and causes of headlight problems:
If the lights are brighter than normal, tell them to look for these.
*High charging system voltage
*Dimmer switch in high beam position
*Flash to pass or high beam relay stuck on
*Bulb problems
*Incorrect setting of automatic dimming sensor
If there is Intermittent operation, check for these:
*Connection issues with switches, fire wall bulkhead connectors ,in-line connectors, head lamp connectors, fuse, or relay blocks
*Weak circuit breakers
*Problems with head lamp relays
*Shorts causing circuit breaker shutdown
*Bulb problems
*Faulty relays
*Faulty switches (headlight or dimmer)
If lights are Dim, check for these:
*Poor grounds
*Contact corrosion in head lamp relays
*High resistance in connections at switches, fire wall bulkhead connectors, in-line connection, headlamp
connectors fuse, or relay blocks
*Bulb problems
If there are no headlights, check for these:
*Bulb problems
*Open or high resistance connection issues with switches, fire wall bulkhead connectors, in-line
connectors, head lamp connectors, fuse, or relay blocks
*Damaged circuit breakers or fusible links
*Faulty relays
*Faulty switches (headlight or dimmer)
*Shorts causing circuit breaker shutdown


Applications/Practice

1 / Refer to content


Evaluation and feedback Prior to Testing or Lab Work

1 / Objective 1. / Formative assessment / Instructor will observe students as they practice the procedure to assure correct procedure and safety practices are being followed. A checklist will be utilized to chart student progress on the task. Questioning techniques will be utilized as necessary to demonstrate student comprehension / Adaptations and/or accommodations for special needs students will be added if required.


STUDENT ASSESSMENT:(Assess student progress with performance criteria.)

1 / Objective 1 / Summative assessment / written test questions on stated objective / adaptation and / or accommodations for special needs students will be added if required
IMPACT--Reflection/Analysis of Teaching and Learning: (How did students’ progress in relation to the state objectives? Was the instruction successful? Analyze samples of student work particularly that which is unsatisfactory, for the purpose of planning further instruction.)
REFINEMENT--Lesson Extension and Follow-up: (To be filled in as the lesson is modified during initial planning and/or during the teaching learning process.)