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Car Flashing SYS, cannot get codes?

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Old Aug 22, 2012 | 11:54 AM
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Default Car Flashing SYS, cannot get codes?

Hey everyone,

I've seen where you can use a paperclip to pull the codes when SYS flashes, but for my car, a '96, it says to put the clip in the two pins that are 4th from the left. It looks like there are only pins in some of the holes on the OBDII plug. I am unsure whether to just stick the paper clip ends in the empty holes or to actually stick it on the ones with the pins.

Also, how do I reset the codes? There was no issue until my battery completely drained and when I jumped it I now have the SYS codes.

Thanks,

Nathan
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Old Aug 22, 2012 | 12:35 PM
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I had the same problem on my 1992 - intermittent flashing "SYS" while driving. Based on several threads I changed the battery and all is OK.

It could be as simple as your battery is not holding charge.
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Old Aug 22, 2012 | 01:00 PM
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Originally Posted by djxib
I had the same problem on my 1992 - intermittent flashing "SYS" while driving. Based on several threads I changed the battery and all is OK.

It could be as simple as your battery is not holding charge.
AND
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Old Aug 22, 2012 | 02:19 PM
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Since the the SYS occurred after letting the battery die, I do think this is probably right, but I still want to see what codes it is throwing. Can I just hook it up to a normal OBDII reader and pull them that way also?

How do I reset the codes to see if they come back?
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Old Aug 22, 2012 | 02:30 PM
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How to get the error codes:

http://corvettephotographs.com/c4vettes/codes.htm
http://forums.corvetteforum.com/1574918379-post18.html
http://forums.corvetteforum.com/c4-t...n-96-cars.html

This tells you what they mean:

http://forums.corvetteforum.com/1576116036-post35.html

I think on the later cars you can just push the RESET button while you're in diagnostic mode to erase the error codes. On early cars you can open the ECM reset connector by the battery:



I have seen some other sources than the above with really good information on this. I need to put it all together. It really needs to be a sticky -- do they still do those?

Last edited by Cliff Harris; Aug 22, 2012 at 02:58 PM. Reason: Added more links.
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Old Aug 22, 2012 | 02:54 PM
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Originally Posted by Cliff Harris
This tells you how to get the error codes:

http://corvettephotographs.com/c4vettes/codes.htm

This tells you what they mean:

http://forums.corvetteforum.com/1576116036-post35.html

I think on the later cars you can just push the RESET button while you're in diagnostic mode to erase the error codes. On early cars you can open the ECM reset connector by the battery:



I have seen some other sources than the above with really good information on this. I need to put it all together. It really needs to be a sticky -- do they still do those?

Thanks I was able to get the codes, but some are not listed.

Here they are:

1. H31, H33, H35, H37
9. H72, H76

On the link you gave there is no code 31. Also the car does seem like it is more reluctant to start.
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Old Aug 22, 2012 | 03:04 PM
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I believe that the error code list was originally posted a zillion years ago by Bruce "Grumpy" Plecan (RIP). It's possible that he missed one. He was a Buick Grand National guy, so Corvettes weren't his specialty. Somebody with a later FSM will have to contribute here.

I edited my earlier post #5 to add some more links.
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Old Aug 22, 2012 | 03:13 PM
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I found this side which explains it pretty well.

http://tech.corvettecentral.com/2011...trouble-codes/

It looks like the codes preceded by H are for history and those with a C are current. I guess this means that those codes came on when my batter died, and that I have no current codes being thrown. Just to be sure I'll probably take my battery in for testing.

Here is a short vid of the codes:


Last edited by nathanours; Aug 22, 2012 at 03:19 PM.
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Old Aug 22, 2012 | 06:27 PM
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Fixed it. I did need a new battery.
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Old Aug 22, 2012 | 06:45 PM
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Old Aug 22, 2012 | 10:23 PM
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Congrats it's always good to get things fixed and just enjoy your car.
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Old Aug 24, 2012 | 12:16 AM
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The ECM remembers the error codes in RAM. That's why opening the ECM reset connector resets them -- it removes the power to the ECM so the RAM gets erased.

I don't know how the newer ECMs work, but on my car the error codes are reset after 50 starts with no errors. If you have current error codes they never get reset.
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Old Sep 2, 2012 | 02:44 PM
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Originally Posted by nathanours
Fixed it. I did need a new battery.
Awesome!
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Old Sep 2, 2012 | 02:46 PM
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Old Sep 3, 2012 | 05:22 AM
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Originally Posted by nathanours
Since the the SYS occurred after letting the battery die, I do think this is probably right, but I still want to see what codes it is throwing. Can I just hook it up to a normal OBDII reader and pull them that way also?

How do I reset the codes to see if they come back?
Glad you got 'er fixed. Just a couple things to consider, should the battery ever get drained again...

In the case of accidental discharge, the car battery can usually (and easily) be salvaged, but it may require some special attention**.

One should never try to charge a deeply discharged battery using the alternator. They're not designed to bootstrap a dead battery, and you run the risk of cooking the diode pack or the voltage regulator in you alternator. Instead, use a battery charger to bring it back up to snuff.

** NOT that you asked, but here's a few things you (or someone) might find useful when it comes to reviving a "dead" battery, i.e., one that was accidently completely drained, even if there is zero voltage across the posts:

The newer "smart (battery) chargers" feature micro-processors and programmed to prevent over charging. They are terrific tools for charging a battery that shows some life (a minimum voltage threshold) and are otherwise in working condition.

However, some "smart chargers" aren't so smart when encountering a "zero volt" situation. If the condition of the battery is below the programming's acceptable threshold, they often prematurely deam the battery to be beyond help. In cases like that, a cheap trickle charger applied over night will bring the battery to a level recognized as acceptible by the sophisticated, high charge rate "smart charger" and it can be used to finish the job w/o over charging and thus cooking the battery.

Of course with the price of gas today, a new battery cost about the same as a tank of premium gas. But, if you happen to have or run across a cheap trickle charger (sans micro-processor), you just might be able to salvage an otherwise good battery. I've revived "dead" batteries (read: a good but severely discharged battery - not one past it's usable lifetime) maybe a dozen times. Just a thought.


P.
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