AT 121 - Lab 2 - Wiring Diagrams
Name: _________________________________ Date: ____________________________________
Using either factory manuals or Mitchell’s on Demand, answer the following questions.
Vehicle - ________________________________________________________
What are the wire colors for the low beam (at the headlight bulb/unit)?
Left __________________________________ Right ________________________________
Which wire is the ground? _____________________________________ (Left)
Which wire is the ground? _____________________________________ (Right)
Does the low beam work? _____________________________________ (Left)
Does the low beam work? _____________________________________ (Right)
What are the wire colors for the high beam (at the headlight bulb/unit)?
Left __________________________________ Right ________________________________
Does the High beam work? _____________________________________ (Left)
Does the High beam work? _____________________________________ (Right)
What are the wire colors for the low beam (at the headlight switch)? _______________________
What are the wire colors for the high beam (at the headlight switch)? _______________________
What is the fuse number and rating for the headlamps? ______________________________________
Does this vehicle have separate fuses for left/right headlamps or high and low beam? ______________
Is this fuse good? _________________________ (use a test light to check)
Is this fuse “hot at all times”? ______________________________
Where are the circuit grounds? _______________________________________________________
What are their numbers? ____________________________________________________________
Are the grounds good? _________________________ (use an ohm meter to check - .5 Ohms or less)
Check the low beam on the left side with the test light, does it have power? ______________________
(Make sure the headlamps are on – and set to low-beam)
Check the high beam on the right side with the test light, does it have power? ______________________
(Make sure the headlamps are on – and set to high-beam)
Based on your findings, is this circuit satisfactory? ___________________________________________
What are the wire colors for the high-stop mount brake light (3 rd brake lamp)?
Vehicle - ________________________________________________________
_____________________________________________________________________________
Which wire is the ground? _____________________________________
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Does the bulb work? _____________________________________
What are the wire colors for the brake lamps?
Left __________________________________ Right ________________________________
Does the brake lamp work? _____________________________________ (Left)
Does the brake lamp work? _____________________________________ (Right)
Are there any other wires on this circuit for the rear running lamps? _________________________
What are the wire colors for the brake lights (at the brake switch)? _______________________
What is the fuse number and rating for the brake lamps? ______________________________________
Is this fuse good? _________________________ (use a test light to check)
Is this fuse “hot at all times”? ______________________________
Where are the circuit grounds? _______________________________________________________
What are their numbers? ____________________________________________________________
Are the grounds good? _________________________ (use an ohm meter to check - .5 Ohms or less)
Check the brake lamp on the left side with the test light, does it have power? ______________________
Check the brake lamp on the right side with the test light, does it have power? ______________________
Based on your findings, is this circuit satisfactory? ___________________________________________
What are the wire colors for the horn?
Vehicle - ________________________________________________________
What is the fuse number and rating for the horn? ______________________________________
Is this fuse good? _________________________ (use a test light to check)
Is this fuse “hot at all times”? ______________________________
Does the low horn work (does it have power?) _______________________________________
Does the high horn work (does it have power?) _______________________________________
Where are the circuit grounds? _______________________________________________________
What are their numbers? ____________________________________________________________
Are the grounds good? _________________________ (use an ohm meter to check - .5 Ohms or less)
Where is the relay located? ____________________________________
Does the relay have power at all times? (Remove the relay and test the cavities with a test light)
________________________________________________________________
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