1st week of brakes

I've gained so much more insight on how the air brake system works. I used to just perform tasks without knowing the functionality/purpose of components. I would build air, release the parking break, change the shoes and components, and adjust the brakes. Now I understand how the S-cam, slack adjuster, and shoes work together to stop a truck. I grasp a lot better what's actually happening when an operator applies the service brake and what could fail.

Knowns and unknows for electrical

There are a few things that I feel comfortable with in electrical:
I feel confidant in finding opens, and that is going to look like a cut wire. You're not going to have any current flow in the circuit.You're not going to have anything at the load on the power side or ground.

High Resistance Voltage Drops are going to be a green corroded wire somewhere in the circuit. You're going to go to your load and not have something close to 12V on the power side and/or 0V on the ground side.

Here's what I need practice on:
Short to powers have always confused me. I understand that it's going to bypass a switch, and an example is you switch something off on the dash but it stays on. What to do after you identify that it's a short to power is where I get fuzzy. I understand that you use an amp clamp in the circuit, but I'm not really clear on the trouble shooting steps.

Short to grounds are a little simpler but still something I don't have a lot of experience with. I understand that it is going to blow a fuse, and that you should use a fuse that glows in it's place (ie a headlight).

Electrical Spring

This week has been a refresher on electrical. The biggest thing I took away from the video on fluke meters was about diode testing. A diode is a one way check valve that provides circuit protection. It' If you get a Out of limit reading on your meter for both directions of the diode then you have an open diode. If your meter reads voltage(~.5V) for both directions of the diode then you have a shorted diode. A very important component that has a diode is the alternator. It can fail if you switch the polarity of the battery by putting the cables backwards or jumping a car incorrectly. A faulty alternator diode can destroy a ECM since there is no longer circuit protection. Another thing I took away from was learning that a solenoid actuates something else. It converts electrical energy to mechanical energy that allows work to be done. An example of this is a magnetic switch which is exactly what a relay is.

Reason for the voltage drop resulting in a dim tail light.

Watched the Fluke instructional video on DVOMs.

3/9

3/2

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2/23

This week what I learned from the most was fixing a license plate light. The most challenging part of it was that it came to the shop with parts of it missing. This made it hard to figure it out by taking it apart. The light was missing and all the wiring was missing/cut so I had no idea where my power and ground came from.

2/16

Since we moved the shop to the new location most of my time has been spent organizing. My main role lately has been getting everything so that the shop runs smoothly and efficiently. There is so much to clean, organize, and figure out that I'm always busy. Besides the shop there's a shed and another storage area attached to the parts room. The entrance to the shed is too narrow for a forklift or a pallet so I've had to get everything in there by hand. The most difficult by far was the steel rack and all the shop steel. The idea was to get it inside so it wouldn't be covered in rust. I also have to go on a lot of parts runs to the local machine shops for flywheels etc. What I've taken away from all this is how to run a very busy shop and keep it moving forward. Since I'm the most familiar where everything is and how the new shop works I get a hundred questions a day. Whether it's the new oil catches, parts washer, how all the filters and oils are setup, how to bleed the airlines of moisture there's always something to have to know.