How to Read Wiring Diagrams

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1971 Mustang Sportroof M code
Attached is a technical training manual from Ford, dated 1968, on how to read wiring diagrams. I got this from the MustangTek website. It's the same one that I got with my Ford manuals, on a CD, but mine is DRM protected.

How to read Wiring Diagrams-Vol-68-S7-L2A_Book-13001.pdf

 

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As a kid, I learned everything I needed to know about electrical by fixing the xmas lights before putting them on the tree.

Just kidding, but I'm sure there are many here that know what I'm talking about....

 
Gents, I need to locate and check if is or is not working, the circuit braker in between lines 37Y and 10, lines feeding emergency flasher and also stop lamp switch, that can be seen at wiring diagram coordinate C-35. How it looks like? I know glass fuses but no these. I can see both cables LG-R H are entering a bound of wires but cannot see where they are coming from. Thanks in advance.

 
The green-red wire runs from the circuit breaker to the 4 way flasher connector and then on to the brakes.  The line 37 is part of an OEM splice deeply buried in the harness: battery power.

If you have brake lights, then the circuit breaker is working.  To test the circuit, simply bypass the circuit breaker, use a jumper cable between the two wires and test for brakes.  Don't do this for long, in case there is a short somewhere. 

 
The green-red wire runs from the circuit breaker to the 4 way flasher connector and then on to the brakes.  The line 37 is part of an OEM splice deeply buried in the harness: battery power.

If you have brake lights, then the circuit breaker is working.  To test the circuit, simply bypass the circuit breaker, use a jumper cable between the two wires and test for brakes.  Don't do this for long, in case there is a short somewhere. 


The green-red wire runs from the circuit breaker to the 4 way flasher connector and then on to the brakes.  The line 37 is part of an OEM splice deeply buried in the harness: battery power.

If you have brake lights, then the circuit breaker is working.  To test the circuit, simply bypass the circuit breaker, use a jumper cable between the two wires and test for brakes.  Don't do this for long, in case there is a short somewhere. 
Thanks Midlife, my problem is that I have no power in the stop switch or the hazard flasher, so need to check the circuit breaker but do not know where is it and how it looks like. Appreciate any other help.

 
Power at the top switch is provided by the auxiliary power harness (black w/yellow dots) running from the by the starter solenoid, across the rear of the engine compartment and through the firewall below the brake booster, terminating in a yellow, three prong female plug housing above and behind where your top switch is. The circuit breaker for this is either on your starter solenoid, or on the terminal block on the fender apron (gauge package cars)

Circuit breaker for the brake lights is above the glove box. 

7172relayplate.jpg

 
Thanks Midlife, my problem is that I have no power in the stop switch or the hazard flasher, so need to check the circuit breaker but do not know where is it and how it looks like. Appreciate any other help.
It is located behind the glove box area and is an approximately rectangular box, about 3/4 x 3/4 x 2.  You'll see two 90* slip-on connectors with the appropriate colored wires on them.

 
It is located behind the glove box area and is an approximately rectangular box, about 3/4 x 3/4 x 2.  You'll see two 90* slip-on connectors with the appropriate colored wires on them.
Ok, thanks midlife, found the colored wires behind the glove box, but the circuit breaker does not exist, was replaced by a kind of fuse box probably by previous owner, and in bad shape, for sure is the reason for my problem.  I was always looking around the fuse box, my mistake. Great!   

 
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