Mastering Diagnostics #14- The Bypass Test

Welcome back to another episode of Mastering Diagnostics with Motor Age Magazine’s Technical Editor, Brandon Steckler. He’s back with another golden nugget to help you along on your path to diagnostic efficiency.

In this episode, Brandon troubleshoots a transmission concern on his 2006 Chevrolet Silverado. The vehicle’s “tow/haul” mode will not function. Brandon takes the time to reference service repair information for a system wiring diagram to first gain an understanding of how the multiple components work together on a data bus to accomplish the goal of “tow/haul mode.”

He then uses the wiring diagram to identify the types of circuits he will be facing and where the components are located on the vehicle. Collectively, with this information in hand, Brandon sits comfortably at his kitchen table to come up with a diagnostic game plan before approaching the vehicle.

As always, Brandon strives to be as efficient as possible. With that, work as little as possible. More time is spent at the computer than is actually spent disassembling the vehicle. It’s this mindset that prevents time from being wasted during the diagnostic process.

Using his Fluke and a few pierce probes, Brandon quickly determines what is functional in the system. He then employs a bypass test to prove the system will function when the prescribed repair is completed. All of this is determined with very little disassembly and only a small amount of time invested.

Stick with Brandon on this episode of Mastering Diagnostics and learn how the bypass test will take your diagnostic efficiency to the next level!

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[ThunderbirdRocket]

You have outdone yourself with this one ! I appreciate the detailed video captures and your thoughtful coaching skills — which are excellent ! Man o’ man that was another super great lesson from yaz’ Brandon ! Seriously / sincerely appreciate you letting us glean off your competency brotha !

[DTEAuto]

Very well explained and being able to show the actual physical break in the wire was a good visual, tying that with the wire diagram testing path helped tie it all together, thanks as always and congrats on the move!

[SEDHACARREPAIR]

THAT HALF AN HOUR VIDEO

MADE MY DAY PRODUCTIVE

THANKS FOR SHARING YOUR EXPERIENCES WITH US IN THIS FIELD

IT HELPS US GROW.

[juttaschierge]

Hi Brandon, this series is excellent and you are a great teacher 🤩

[mikechiodetti]

Yup. Seen this before but on the Ford F250/F350 steering column. Ford put the wires up through the selector handle to the OD switch. Where the wires entered the selector handle hole the metal is not smooth, the wires are pulled tight and the wires are not covered/protected. Talk about triple jeopardy, planned obsolescence!
So I was able to add some protection to the wires, then I lengthened the wires for less bending and mounted them to eliminate the tight pulling by routing them a little differently.
It worked. Never had a comeback.
Thank you for this video.
If you question the engineering design, the engineers would tell you "We've NEVER had any problems with our design."
O course not! But then, they never tested the vehicle for 10 years/150, 000 miles, Summer and Winter, humid and dry.
If they saw what I did for the repair, "Oh we can't do that!" "That extra wire, plus the 2 cable ties would add at least $1.00 to the wholesale cost of building the vehicle. Added to 10, 000 built vehicles, that's lost profit!"
But don't worry. We can manufacture "replacement parts" to fix the vehicle for maybe 10 years.
UHUH!

[dude]

Learning Fundamentals is 🔑 .Thank you Brandon. Btw I love the lost river In Lincoln NH

[mikeburdi]

Great little tutorial / refresher Brandon. Keep 'em coming and we'll keep on watching!😅 Seriously, thank you buddy. I know these videos take up a lot of time and they are not as easy to put together as some of us might assume. So thank you!

[anthonysova]

THANKYOU I used this video to explain why electrical and mechanical diagnosis is different My friend would complain why I used your approach (finally understanding why) Convincing him electrical diagnosis may take research and time but the repair time is minimal. Congrats on the move Your videos are excellent CHEERS

[spirokattan]

All the best in NH Brandon! Thanks for another great lesson.

[jordysandino]

Thank you Mr Brandon as always we apréciate you esfuerzo

[DJ-tnvj]

Congratulations B. Appreciate the information as always.

[mikejr]

Congratulations on your move. I lived in NH for many years and there are some stunning areas to visit. Great tip showing the bookmark feature, I'll be using that from now on.

[Grunter]

Thankyou Brandon informative as always.

[pakautomotivetp]

great explanation and creativity came into see in diagnosis strategies. Thanks mate

[GroundedDiagnostics]

Gotta love the game plan.. as all ways a very well put together video. congrats on the new place 😊😊👍👍

[danielgarage]

Wow, what great video with such good explanation. Thank You!

[lupedelacruz]

Well done amigo thank you very much for sharing

[nickayivor]

Enjoy your weekend with all your family around you, BRANDON STECKLER MOTOR AGE
Can't wait for the next training video
👍
WHIP SMART, BRANDON STECKLER MOTOR AGE
From Nick Ayivor from London London UK 🇬🇧 ⏰️ 23:46PM Good Evening

[sheerwillsurvival]

Great video. If you could find the time to do a video on how a 5volt reference system works. Like how it uses a generator or something to make multiple 5volt references for multiple sensors. I can’t get my old brain around how it works. Like don’t all those sensors take part of the voltage for the 12volt system 😵‍💫🙋🏼‍♂️🙇🏼‍♂️🤦🏼

[kylefentz]

Why was MotorAGE magazine discontinued? Really liked that magazine