SYS light flashing - just replaced battery.

[sexasomniac]

I have no codes stored and I just replaced my battery this weekend. When I changed my battery the outside of the terminal bolts were corroded looking but my dad cleaned everything up with a wire brush and the car is reading normal voltage. I'm still thinking of replacing the terminal bolts as a starting point. I also think it may be a loose ground or wire to the alternator/starter. What do you guys think??? Want this light to go away.

 

[Robertwav1]

How about checking the grounds along the frame rails accessed from under the hood, look along the rail. Grounds under the car around the bell housing. And if I'm not mistaken a major connection site behind the battery that may be +. I was supprised how bad these were on my 93. Cleaned them all. Good place to start if you suspect a ground issue.

 

[sexasomniac]

Thank you! I searched on three forums for two days and this is the first kind of answer I'm looking for. After starting issues today it is definitely a loose wire somewhere going to either the distributor or ignition so I'm going over them all this weekend and hopefully that will take care of it.

 

[9340Ruby]

Thank you! I searched on three forums for two days and this is the first kind of answer I'm looking for. After starting issues today it is definitely a loose wire somewhere going to either the distributor or ignition so I'm going over them all this weekend and hopefully that will take care of it.

Did you happen to figure out the "SYS" problem? I had that same problem, but mine was the Driver information Center. I don't think this is your problem. I knew the DIC was working correctly because the buttons for information would only work when it was cool. I guess the heat expanded and caused the "SYS" light. Hope everything works out for you as I know this can be frustrating!!

 

[sexasomniac]

Thanks for asking about the follow up. I actually did find out what it was today... haha. I was still having problems and was getting frustrated so as a last desperate attempt I tried tapping on the ECM to see what would happen while the car was running. Sure enough... the light went out.. tapped on it again and the light came right back on. I just replaced the ECM so I'm thinking its a bad PROM, it is not seated correctly in the MEM-CAL, or the new ECM is also faulty, atleast I know where the problem is!!! I'm so relieved.

 

[9340Ruby]

Well I know you are relieved that you do know the problem.

 

[Paul Higg]

New to site, & SYS lite.

My first Vette! I have waited years for my turn to own a Vette. I have a 1994 LT1 and I have a dreaded SYS light. Here's when it comes on.

1) Whenever I start it.
2) If the car is not running and I have the ignition on and turn the lights on and off.
3) Whenever the voltage indication is above 14.3.
4) Random times.

I have a brand new battery that was just installed last week by Corvette Country in Fayetteville, GA, these guys really know their stuff. I was told by the senior mechanic that it could be a bad serpentine belt.

I bought the entire shop service manual but haven't had time to read it yet, just got back from Tybee Island on my anniversary.

Can anyone recommend a good analyzer and where to buy it?

Thanks a lot.

Paul

 

[JAKE]

You can ground the ALDL under the driver's side of the dash with a short length of wire, then follow the directions in the FSM to show what's causing the "SYS" light to flash.

I'd first clear the code causing the a 'SYS' light to flash then wait to see if it comes back. If it does, the FSM will show you what the code means and you can track down the cause from there.

The FSM will show you which buttons to push, etc.

Jake

 

[Paul Higg]

Thanks Jake. I will look in the manual. I have been very busy and the manual is five binders wide. I have a LOT to learn and I am grateful for all of you people's support.

Paul

 

[JAKE]

Thanks Jake. I will look in the manual. I have been very busy and the manual is five binders wide. I have a LOT to learn and I am grateful for all of you people's support.

Paul

In the GM Service Manual for the 96 Vette, the procedures for pulling the 'SYS' codes from the Central Control Module begins in Section 8D. The procedure on doing the Diagnostic begins on 8D-4. All the codes are listed in that section.

Of course, that's for the 96, so your specific section may differ. Hope this helps.

Jake

 

[Paul Higg]

Thanks Jake, I have been going through the manual page by page and taking notes to what pertains to what needs to be fixed. I haven't gotten that far yet but I will soon enough. I appreciate your help.

Paul

 

[JAKE]

Thanks Jake, I have been going through the manual page by page and taking notes to what pertains to what needs to be fixed. I haven't gotten that far yet but I will soon enough. I appreciate your help.

Paul

Okay. Keep us posted on how you're making out.

Jake

 

[Paul Higg]

Well, after MUCH hassle I managed to replace a worn serpentine belt today. It was a HUGE hassle. Good thing Advance Auto rents a long 16 mm wrench. Anyone else ever replace one? Any suggestions as to how to make it easier? I followed the FSM but it was STILL a pain. The old one must have been stretched like a woman giving birth because it came off easy.

Paul

 

[Paul Higg]

By the way, I had the guy at the auto parts store put his meter on my diagnostics plug, it seems like I have a cross between an OBD 1 and an OBD 2 plug. We found no codes but I didn't think so with the SYS light. Still busting my head with that one but I suspect by the way it's acting that it is an electrical problem.

As soon as I changed the belt my voltage went from a usual 14.7/14.5 to 14.1. Dunno if that means anything but I still had the SYS light when I started it. I will get to the bottom of it sometime though. Thanks for the encouragement.

Paul

1994 LT1 coupe

 

[JAKE]

I have a 96 and changing belts is pretty easy for me. When I installed the 388 I built with the SuperDamper, I had to come up with a different length belt. So I had to install and remove belts a few times until I found the correct length belt that would work with the new and different damper.

I just used a 1/2" ratche and socket (I forgot with size) and I put an extension (like a length of metal tubing/pipe) on the handle of the ratchet to give me more leverage. Then I just crank on the tensioner bolt and BINGO! Takes less than 5 minutes.

I've never had anyone try to pull 'SYS' codes using a scanner or reader. I just use a short piece of wire, jumper terminals 12 and 5 on the under dash link. Turn the ignition key to the "ON" position but don't start the engine.

On the 96, the terminal #12 is on the lower row, fourth from the left. Terminal #5 is on the upper row fifth from the left. Jumpering those two puts the CCM (Central Control Module) in Diagnostic Mode once the key is turned to the "ON" position.

Then I just use the TRIP/ODO and ENG MET buttons to cause the Modes and stored codes to display on the dash cluster. Once the code(s) pops up, I use the manual and look up the code to find the problem and how to fix it.

Your year Vette may be a bit different, but I'll bet it's close. Your FSM will show you.

Jake

 

[Paul Higg]

Thanks Jake, I will have to learn how to use the FSM to jumper and look for the codes. I will also have to learn how to use the TRIP/ODO & MET/ENG buttons for that. Arrrgghhh! So much to learn! It took me 25 years of experience to troubleshoot B767 avionics systems, I have three weeks under my belt so far. I have to have patience.

 

[sexasomniac]

Haha, yeah. My mom said the only good thing coming out of my car having problems is how much I'm learning after buying my FSM and reading on here.

 

[Paul Higg]

No kidding. You can learn a LOT from the FSM, especially if you have a troubleshooting background. But what really helps the most is people's experience here on the forum, it beats the FSM and experience hands down.

 

[JAKE]

Thanks Jake, I will have to learn how to use the FSM to jumper and look for the codes. I will also have to learn how to use the TRIP/ODO & MET/ENG buttons for that. Arrrgghhh! So much to learn! It took me 25 years of experience to troubleshoot B767 avionics systems, I have three weeks under my belt so far. I have to have patience.

Do you want me to list the procedure for pulling the codes? I can only list it for the 96 though.

Jake

 

[Paul Higg]

YES! Jake, that would be helpful if you don't mind. I thought I had it licked after the serpentine belt change, it didn't come back on at all, then all of a sudden, whammo, as soon as I turned on my left blinker to go into my subdivision, the darned SYS light came back on.

You know what is strange? I was waiting for my wife in a parking lot and I decided to pull a fuse to see if the chimes fuse was dead. Well it was the same fuse that controlled the speedo and the other indications, it wasn't burned out but ever since I have had that annoying indication. I drove all the way to Savannah and back last week and it was intermittent. It seems to be related to some electrical problem. I just KNOW it. I might also have to look into the battery terminal terminations on the chassis as I had a new battery installed in it and they did an excellent job of cleaning the terminals. Finding the other ends will be a chore though.