ABS Controller Multiple Diagnostic Code Storage Order?

[bill190]

So far as ABS controllers and multiple diagnostic codes being stored in its memory...

Are these codes stored in any order? Like first code to display would be the oldest code stored?

Or the other way around. The first code displayed would be the newest code stored into the memory?

(Specifically a 94 GMC 1500 K Suburban with 4 wheel anti-lock brakes. But also in general.)

 

[MikeHalloran]

I don't think there's a statutory requirement that codes be presented in temporal sequence.

The factory shop manual should tell you more.



Mike Halloran
Pembroke Pines, FL, USA

 

[bill190]

Actually I have 4 factory shop manuals for one vehicle and 3 factory shop manuals for another and they don't say a thing about this.

These manuals could do a better job of explaining how electronic things work in general.

 

[crazychris]

trying to remember from my computer days, since the processor is simple it's probably a first in first out load.
can be first in last out??.

Why do they charge co much for old outdated computers with
limited functionality and programmability.

Stick in a dual core with 4gig ram and software with vehicle management software.
on the fly programming and modifications.

 

[GregLocock]

Big clue - they don't pay what you pay for an EEC

Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[mattsooty]

" on the fly programming and modifications "

Not directed at you personally, Crazychris, but I always laugh at how some people think that they can do a better job than the OEM engineers that developed these systems in the first place.

MS

 

[MacGyverS2000]

Why do they charge co much for old outdated computers with limited functionality and programmability.

Stick in a dual core with 4gig ram and software with vehicle management software. on the fly programming and modifications.

Yes, because I want Windows CE controlling the safety features of my car...

Dan - Owner

http://www.Hi-TecDesigns.com

 

[NormPeterson]

. . . old outdated computers with
limited functionality and programmability.

For the system under discussion here, it has a rather limited function and the processor is apparently fast enough to get the job done. No point in bloating it to give it potential capabilities it won't ever need or use. Nor do I see much reason to tweak this particular system in this particular vehicle.

As for "on the fly programming and modifications", I'm sure that there are certification, durability, and tampering issues at stake if I may assume that you were including ECM/PCM "tuning" at that point.


bill - the diagnosis logic for one of the codes may ask if others are present at various decision points. If that is the case, the order in which the codes were stored may not matter.


Norm

 

[bill190]

That interesting about the logic looking for other codes present. And certainly a good way for the computer to determine what the problem may be!

This would be handy to know with a used vehicle which may have old diagnostic codes "hanging around" from problems which were fixed a long time ago, but the codes possibly not cleared.

In this case see which codes are present (write them down), then clear all codes, then drive vehicle and see which new codes pop up. See if they are different or the same.

And of course if this had been your vehicle for a long time and you knew all the previous codes (if any) were cleared, then this would not be necessary. But of course clear the codes after the problem has been resolved.