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Trouble with SYS warning, please help...

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Old Apr 27, 2011 | 05:53 PM
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Default Trouble with SYS warning, please help...

I hooked up a new radar detector to my '93 Corvette. It worked fine, but I started getting a SYS warning in the speedo area. I disconnected the radar detector and everything (except the rd) worked fine with no SYS warning.

I had hooked up the rd to a 12 V and a ground in the rear view mirror, and I thought that might be the problem.

So, re-hooked it up to the fuse box on passenger side. First I tried #27 " instrument cluster" and then #19 "Utility" (both switched so I could leave the rd on all the time and it would go on and off with the ignition), but both times, after making the connection, closing the doors, and starting the car, I got the SYS warning. Then I disconnected the rd and I STILL got the SYS warning? What the heck?

So, having spent hours going through other people's similar problems, trying to find an answer, I realized there might be a stored Trouble Code setting off the SYS. So I did the scan for codes, and all I got was the standard "12", which is the start and finish sequence of the program.

Then I thought, what the heck, let me disconnect the negative terminal of the battery and try to have an automatic reset of everything. I did that, but it did not work. I still get the SYS warning every 15 seconds when the engine is running.

Does anyone have any ideas what could be causing the SYS warning to come on and how can I get the SYS light from coming on (without disconnection)?????

Steve Nix
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Old Apr 27, 2011 | 06:20 PM
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I'd put my money on a failing battery. Have it tested.
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Old Apr 27, 2011 | 07:04 PM
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Originally Posted by Steel Blue 91
I'd put my money on a failing battery. Have it tested.
Probably the problem...how old is the battery?
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Old Apr 27, 2011 | 08:01 PM
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The battery just hit being 4 years old. However, after sitting for 3 hours after getting home from work, I'm getting a voltage reading of 12.67 Volts which is strong.



Originally Posted by bac22
Probably the problem...how old is the battery?
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Old Apr 28, 2011 | 05:32 AM
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Drive the car for 15 minutes, turn off and back on. I get sys from time to time after the car sits and the battery gets low...
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Old Apr 28, 2011 | 05:58 AM
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I seem to remember something about a radio swap causing this as well. Have you changed the Delco for an aftermarket?
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Old Apr 28, 2011 | 09:47 AM
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No, the radio/sound system is stock.

Also, after sitting for 15 hours I'm getting a 12.54 Volt reading from the battery, so it is pretty doubtful that the battery is the reason for the SYS message.

Thanks for the tries, guys, but we haven't hit on it yet. I would think SOMEONE has the knowledge of what else to try?



Originally Posted by Steel Blue 91
I seem to remember something about a radio swap causing this as well. Have you changed the Delco for an aftermarket?
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Old Apr 28, 2011 | 10:22 AM
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Originally Posted by SteveNix
No, the radio/sound system is stock.

Also, after sitting for 15 hours I'm getting a 12.54 Volt reading from the battery, so it is pretty doubtful that the battery is the reason for the SYS message.

Thanks for the tries, guys, but we haven't hit on it yet. I would think SOMEONE has the knowledge of what else to try?
the radio causes it in my c4 also mine goes off everyonce in a while beause i am not using the bose speakers with the onboard amp
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Old Apr 28, 2011 | 05:51 PM
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Hey guys, this is driving me crazy. The SYS displays every 15 seconds, knocking out whatever I was monitoring. Someone, somewhere must have something else to try besides the battery or the radio????

I know electrics are tough, but someone must have run into this before?

It's worth $100 to me for some guidance to get this fixed. I do not want to go to the dealer.

Thanks.

Steve Nix
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Old Apr 28, 2011 | 06:20 PM
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it has to do with a resistance drop in one of the fuses operating the radio and other instrument panels.
Once I replaced my stock radio with an after market one, the same exact thing happened to me. I remember researching it yrs ago and remember the way to fix it for the radio at least was to put a resistor in line one of the wires coming out the back of the radio going into the fuses to trick the computer into not letting it think it was loosing current.
I think it may have had to do with the conversion of the dimming switch wire on the stock radio to a newer radio since after market decks do not dim with the rest of the interior lights.
Im not sure how it is with the radar detector but im pretty sure its relevant to that same issue...
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Old Apr 28, 2011 | 06:21 PM
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check this out, might work
http://forums.corvetteforum.com/audi...u-install.html
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Old Apr 28, 2011 | 08:25 PM
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Wow, now that makes sense to me. I had heard that hooking up to existing lines could cause problems. I'm perplexed however, why I still get the SYS warning when I disconnect the Radar Detector????

If it corrected by disconnecting the RD, then I would jump right in with trying the resistors, but I can't get the SYS light off when it is not even connected. I have to find a way to get the SYS light off with the RD disconnected, and not hooked up at all, right?

Thanks so much, though, that effort is appreciated!

Steve Nix


Originally Posted by mcsports965
it has to do with a resistance drop in one of the fuses operating the radio and other instrument panels.
Once I replaced my stock radio with an after market one, the same exact thing happened to me. I remember researching it yrs ago and remember the way to fix it for the radio at least was to put a resistor in line one of the wires coming out the back of the radio going into the fuses to trick the computer into not letting it think it was loosing current.
I think it may have had to do with the conversion of the dimming switch wire on the stock radio to a newer radio since after market decks do not dim with the rest of the interior lights.
Im not sure how it is with the radar detector but im pretty sure its relevant to that same issue...

Last edited by SteveNix; Apr 28, 2011 at 08:54 PM.
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Old Apr 29, 2011 | 10:59 AM
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OK, no radar detector connected. No trouble codes have been set. The negative battery connection was disconnected to reset all base values and then reconnected. Stock and unmolested radio/stereo/cd. The battery is strong. There is nothing hooked up to any fuses to cause a voltage drop.

How can I get this SYS warning from appearing every 15 seconds????
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Old Apr 29, 2011 | 06:29 PM
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I still say battery, but here's a few things to check out. First see what the car is drawing for power while off, doors closed, nothing on. Do this by removing the negative battery cable, set your multimeter up to read amps. Put 1 lead of the meter on the negative battery post and the other lead of the meter on the negative cable. Read the current draw, shouldn't be more the 50mA or .050 amps.

Next do a load test on the battery where fully charged. Hold the leads of the volt meter to the corresponding battery terminals and watch the volt meter while someone else starts your car. Make a note of how low the battery voltage drops. A normal car battery will drop to 10 or 11 volts. If your battery voltage drops below 10, this is a sign that it needs to be replaced.

My car has been sitting for 2 weeks in 40-50 degree weather and my battery is reading 12.37 volts, yet your's dropped to 12.54 in just 15 hours....that drops seems higher then is should be for 15 hours.
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Old Apr 30, 2011 | 09:55 PM
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Thank you, very good suggestions! I would love to eliminate the battery as the cause, and this should do it, one way or the other.

I'll try it tomorrow afternoon when I have some personal time available.

Thanks again, I appreciate the thought and effort.

Steve Nix


Originally Posted by bac22
I still say battery, but here's a few things to check out. First see what the car is drawing for power while off, doors closed, nothing on. Do this by removing the negative battery cable, set your multimeter up to read amps. Put 1 lead of the meter on the negative battery post and the other lead of the meter on the negative cable. Read the current draw, shouldn't be more the 50mA or .050 amps.

Next do a load test on the battery where fully charged. Hold the leads of the volt meter to the corresponding battery terminals and watch the volt meter while someone else starts your car. Make a note of how low the battery voltage drops. A normal car battery will drop to 10 or 11 volts. If your battery voltage drops below 10, this is a sign that it needs to be replaced.

My car has been sitting for 2 weeks in 40-50 degree weather and my battery is reading 12.37 volts, yet your's dropped to 12.54 in just 15 hours....that drops seems higher then is should be for 15 hours.
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Old Apr 30, 2011 | 10:46 PM
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When I got my vette it started fine but had the SYS also. Replaced the battery and problem was fixed.

You ask for advice so try it at least. Buy a battery from Autozone and install in the car temporally carefully by just sitting it in there. According to your facts you should know in 30 seconds if it makes a difference.
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Old May 1, 2011 | 04:10 PM
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OK, bac22 -I got a chance to do the 2 tests a few minutes ago. I was a little confused because I had Micro amps, Milli amps, and Amps on my multimeter and I tried all three, getting these readings:
micro amps - .5-.6
Milli amps - .05-.06
Amps - .01-.03

I'm thinking that I may have gotten a higher reading on Amps because that was as low as it would measure?

My voltage on the battery dropped to 10.96 Volts when I started the car.

So, the battery looks pretty good, and doesn't have much of a draw when off, right?

I did find ONE other possible culprit when I unhooked the negative terminal to the battery. I forgot I have a transponder hooked directly up to the battery. And there is an On-Off switch that I normally have off except when I go to the track, but could that be it? I removed the negative connection from the transponder to the battery.

Then I re-hooked up the OEM negative battery connection and restarted the car. Absolutely no difference. I still get the SYS every 15 seconds.

pcolt94, I'm almost at the point where I will take your suggestion and just get a new battery to try it, but I hate to do that when everything looks pretty good with the battery. Never a problem, never a slow start or even hesitation when starting. the car runs great, it just gives me a SYS warning every 15 seconds and it is driving me crazy.

Thank you for the suggestions you have made, I appreciate every one, but just can't get a handle on this. Anything or anybody else?????

Steve


Originally Posted by bac22
I still say battery, but here's a few things to check out. First see what the car is drawing for power while off, doors closed, nothing on. Do this by removing the negative battery cable, set your multimeter up to read amps. Put 1 lead of the meter on the negative battery post and the other lead of the meter on the negative cable. Read the current draw, shouldn't be more the 50mA or .050 amps.

Next do a load test on the battery where fully charged. Hold the leads of the volt meter to the corresponding battery terminals and watch the volt meter while someone else starts your car. Make a note of how low the battery voltage drops. A normal car battery will drop to 10 or 11 volts. If your battery voltage drops below 10, this is a sign that it needs to be replaced.

My car has been sitting for 2 weeks in 40-50 degree weather and my battery is reading 12.37 volts, yet your's dropped to 12.54 in just 15 hours....that drops seems higher then is should be for 15 hours.
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Old May 1, 2011 | 07:36 PM
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Originally Posted by SteveNix
micro amps - .5-.6
Milli amps - .05-.06
Amps - .01-.03
Something doesn't seem right with those numbers. 50mA is equal to .05A. So when you had your meter set in mA (milli) you should have seen 50 and not .05. The numbers seem like the meter wasn't reading amps, but was just drifting. You did have it in series (between) with the negative cable and negative battery post?

One way to make sure you are reading the meter right is set it to straight amps and open the door so the interior lights come on, you should see a couple of amps being drawn when you do that.

My voltage on the battery dropped to 10.96 Volts when I started the car.
Seems the battery is okay, the question now is to make sure that there isn't a short somewhere causing a current draw on the battery which continually lowers the overall battery voltage.

I did find ONE other possible culprit when I unhooked the negative terminal to the battery. I forgot I have a transponder hooked directly up to the battery. And there is an On-Off switch that I normally have off except when I go to the track, but could that be it?
Possibly, maybe it's drawing too much current when it's active. Turn it off and run the car for a while with the "SYS" flashing, sometimes it takes several trips for "SYS" to clear out.


pcolt94, I'm almost at the point where I will take your suggestion and just get a new battery to try it, but I hate to do that when everything looks pretty good with the battery.
Before doing that you really need to get a good reading on current draw to make sure it's in spec. Otherwise you're going to have the same problem.
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