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RWD - '93 with horn issues

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'93 with horn issues 200

Hi,

I will give this a kick up to the top again to see if you can get more responses.
I personally have not looked into your question or know much about it, so that makes me a salt shaker, with those grains of salt to ignore!

With that said I would say why not take the precautions. Undoing the battery negative shuts down everything and only takes a few seconds.

On my 1993 there is a tiny sticker on the drivers side strut tower, putting out a caution on working on the SRS system. So there is something around there, probably connectors, that worry them. It's also in most manuals.

Now this is what makes me wonder about airbags, that are not suppose to deploy, if the vehicle is below a certain speed like 15 mph.
The same thing is like the cruise control that should not engage below 35 mph.
Both these systems work this way when being used.
The concern is a possibility of residual charge feeding back into components or if someone puts a connection back to power somewhere else, that the engineers have not thought of or tested for.

Sort of like a rush to market within software.
An Example is in the 737 max airliner right now!
An Interpretation of the inclination sensor into a program line, that leads to other programming lines and a loop gets started!

In my days of CNC, it was called a "CANNED" protocol! A standard routine procedure that gets repeated by a short command line or word!
In this case, the autopilot program is missing or is misplaced with an, "if" line of program, to buffer a miss calibration of or a perimeter input signal from something elsewhere.
This maybe missing in another section of the main program or in both places!
The "if" is a negation fix or override!
The same concept is used in the cruise control, ABS, SRS etc.

So if you are poking around in the steering wheel, looking for broken parts or connections, it's best to have things dead.
You can used a voltmeter/ohmmeter that has very low voltage and amperage batteries inside.

On the newer BUS system cars, you are not so lucky, as many things that get activated through a larger black box that sends signals out to several components on only one wire and that one may even power it! This cuts down on "cost" of making the large wiring looms, connectors and corrosion.
But there are several trade offs!
Each component talks back and forth and requires using very small amounts of power, all the time.
That's why a scan tool (a wire tapping or looking device) is required to play in that arena!
Otherwise, it gets to be a challenging project of doing logical thinking of how the systems have a procedure "of order" that needs to be on or off communication status.
No signal to or a no response or is it a no power or an out right failed component.
Again, it can be a terrible trade off!

That's when it gets to becoming a Remove & Replace (R&R mechanic) that's guessing with your pocket book.
For years now, to be a mechanic you have to be part programmer and learn lots of abbreviations!

Ok that my salt with a little black pepper mixed!
(:-)
Phil






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New '93 with horn issues [200]
posted by  Huffybrick  on Wed Mar 20 13:42 CST 2019 >

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