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Occupational Title: Heavy Equipment Maintenance Technician
Key Purpose: Diagnose, service and repair heavy equipment
Critical Work Function
3 Diagnose, service, and repair vehicle electrical and electronic systems 		Occupational Skills, Knowledge and Conditions
Key Activities
Performance Criteria
Occupational Skills and Knowledge
Conditions
Those duties or task clusters that are necessary to perform each critical work function.
Specific demonstrable performance and standards that indicate when the key activity has been performed successfully.
Those skills and knowledge that are specific to the occupation, such as technical processes or procedures common across the occupation that are critical to the related key activity.
Tools, resources and equipment necessary to carry out key activities and their related performance criteria.




KA 3.1 Perform diagnosis of general electrical and electronic systems.
Number
Criteria
3.1.1 Check continuity in electrical/electronic circuits, components, and parts.
3.1.2 Check applied voltage, circuit voltages, and voltage drops.
3.1.3 Check current flow.
3.1.4 Check resistance in circuits, components, and parts.
3.1.5 Find opens, shorts, and grounds.
3.1.6 Diagnose key-off battery drain problems.
3.1.7 Inspect, test, and replace fusible links, circuit breakers, and fuses.
3.1.8 Inspect, test, and replace diodes and resistors.
3.1.9 Post-service vehicle performance indicates system components performing at or above OEM specifications.
Knowledge and understanding of basic electrical theory and electric circuits

Knowledge of electrical and electronic system components and parts and their function in the system

Interpret wiring diagrams and schematics

Understand and interpret testing procedures, test meters, and electrical test equipment

Knowledge and usage of shop manuals and other appropriate documentation

Using the following tools, resources and equipment:

Industry-approved electrical-system diagnostic tool

Common mechanic’s hand tools

Wiring diagrams and schematics

Appropriate shop service manuals and other documents

KA 3.2 Maintain and service batteries.
Number
Criteria
3.2.1 Determine the correct size and number of batteries for a vehicle.
3.2.2 Remove and install, clean, and replace batteries.
3.2.3 Determine battery state of charge by measuring terminal voltage using appropriate tools.
3.2.4 Inspect, clean, repair, and replace battery cables and connectors.
3.2.5 Charge battery using slow and fast method.
3.2.6 Inspect, clean, repair, and replace battery boxes, mounts, and hold downs.
3.2.7 Jump start vehicle using jumper cables and a booster battery or auxiliary power unit.
3.2.8 Dispose of batteries and battery electrolyte.
3.2.9 Post-service vehicle performance indicates system components performing at or above OEM specifications.
Knowledge of different types of batteries appropriate to vehicle

Understand procedure to charge a battery

Understand correct jump-start procedures

Understanding and usage of PPE and safety precautions.

 Using the following tools, resources, and equipment:

Electrical-system diagnostic tool 

Jumper cables

Booster battery/auxillary power unit

Distilled water

Appropriate battery service tools

Battery application charts

KA 3.3 Diagnose, service, and repair starting system.
Number
Criteria
3.3.1 Perform starter current draw test and determine needed repairs.
3.3.2 Perform starter circuit voltage drop tests and determine needed repairs.
3.3.3 Remove and replace starter.
3.3.4 Inspect, test, and install/replace starter relays, solenoids, and switches.
3.3.5 Inspect, test and replace components and wires in the starter control circuit.
3.3.6 Disassemble, test, and repair starter.
3.3.7 Remove and replace flywheel ring gear.
3.3.8 Post-service vehicle performance indicates system components performing at or above OEM specifications.
Knowledge of starter operating principles, parts, components and their function

Knowledge of various types of starting motors and starting systems

Knowledge and usage of shop manuals and other appropriate documentation

Using the following tools, resources, and equipment:

Appropriate testing equipment

Common mechanic's hand tools

Soldering gun/iron

Appropriate shop service manuals and other documentation

KA 3.4 Diagnose, service, and repair charging system.
Number
Criteria
3.4.1 Diagnose the cause of no charge, low charge, or over-charge condition and/or indicator light problems and determine needed repairs.
3.4.2 Perform charging system output test and determine needed repairs.
3.4.3 Perform charging circuit-voltage drop test and determine needed repairs.
3.4.4 Remove and install/replace alternator/regulator.
3.4.5 Inspect, adjust, and replace drive belts, pulleys, fans, and mounting brackets.
3.4.6 Inspect and replace direct drive couplings and gears.
3.4.7 Disassemble, test, and repair alternator.
3.4.8 Inspect, test, repair, or replace connectors and wires in the charging circuit.
3.4.9 Diagnose the cause of brighter than normal, intermittent, dim, or no headlight operation.
3.4.10 Post-service vehicle performance indicates system components performing at or above OEM specifications.
Knowledge of charging system operating principles

Knowledge of alternator parts and charging system components and their function

Knowledge of various types of charging systems

Knowledge of various types of field circuits

Knowledge and usage of shop manuals and other appropriate documentation

Using the following tools, resources, and equipment:

Appropriate testing equipment

Common mechanic's hand tools

Belt tension gauge

Appropriate shop service manuals and other documentation

KA
3.5 		Diagnose, service, and repair lighting systems.
Number
Criteria
3.5.1 Test, aim, and replace headlights.
3.5.2 Test, repair, and replace headlight and dimmer switches, wires, connectors, and sockets.
3.5.3 Inspect, test, and replace switches, bulbs, sockets, connectors, and wires in tail light circuits.
3.5.4 Post-service vehicle performance indicates system components performing at or above OEM specifications.
Knowledge and understanding of lighting systems

 Understanding and usage of diagrams and schematics

Knowledge and usage of shop manuals and other appropriate documentation
 Using the following tools, resources, and equipment:

Appropriate service tools and testing equipment

Common mechanic's hand tools

Appropriate shop service manuals and other documentation

KA
3.6 		Diagnose, service, and repair monitoring systems.
Number
Criteria
3.6.1 Diagnose the cause of intermittent, low, or no gauge readings and determine needed repairs.
3.6.2 Test and replace senders and sensors.
3.6.3 Inspect, test, replace, and calibrate electronic speedometer, odometer, and tachometer systems.
3.6.4 Post-service vehicle performance indicates system components performing at or above OEM specifications.
Knowledge and understanding of monitoring systems

Knowledge of PC usage and OEM diagnostic software

Understanding and usage of diagrams and schematics

Knowledge and usage of shop manuals and other appropriate documentation 		Using the following tools, resources, and equipment:

Personal/laptop computer

Diagnostic software

Appropriate service tools and testing equipment

Common mechanic's hand tools

Appropriate shop service manuals and other documentation

KA
3.7 		Diagnose, service, and repair accessory systems.
Number
Criteria
3.7.1 Diagnose the cause of constant, intermittent, or no warning-device operations and determine needed repairs.
3.7.2 Diagnose the cause of constant, intermittent, or no wiper operations and determine needed  repairs.
3.7.3 Diagnose the cause of wiper speed control and/or park problems and determine needed  repairs.
3.7.4 Inspect and replace wiper motor transmission linkage, arms, and blades.
3.7.5 Inspect, test, and replace windshield washer motor or pump/relay switches, connectors, and wires.
3.7.6 Inspect, test, and replace mirror heater circuit grids, relays, switches, connectors, and wires.
3.7.7 Inspect, test, and replace manufacturer/or other dealer-installed electrical accessories, integral fuses, connectors, and wires.
3.7.8 Diagnose cause of slow, intermittent, or no power side window operation.
3.7.9 Post-service vehicle performance indicates system components performing at or above OEM specifications.
Knowledge and understanding of accessory systems

Knowledge and application of appropriate measuring instruments

Knowledge and usage of schematics

Knowledge and usage of shop manuals and other appropriate documentation

Using the following tools, resources, and equipment:

Appropriate service tools and testing equipment

Diagnostic tools

Common mechanic's hand tools

Appropriate shop service manuals and other documentation