SYS flashing.

[Enzo]

During a ride SYS starts flashing, alternating with the aver/inst display, left of the fuel gage. OM says there is a problem with one of the CCM-controled systems. Have the vehicle checked by a dealer. Any idea of what that message means?

 

[Enzo]

What a coincidence! Just after I posted I saw a thread about the same problem. I'll have a look at all the answers and see if I can get any clue.

 

[ecss]

On a 91 short pin A to pin G. Turn ignition On. Look at dash cluster LCD.

Module 1 is for the CCM --- indicates no errors
Module 4 is for the ECM --- indicates no errors
Module 7 is for active suspension ERR is normal

C12 indicates diags. are running.


Diag. connector above drivers right knee looks like this.

[F|E|D|C|B|A]
[G|H|J|K|L|M]

 

[Paul Higg]

Did you just replace the stereo?

What diag codes did you get?

Paul 94 LT1

 

[Enzo]

I did'nt replace the stereo and dind'nt check the codes yet. I'll try to check. Thank you.

 

[Paul Higg]

Do you have an FSM?

 

[Enzo]

Yes. I have the FSM, but my technical skills are not that good. Today I drove the car for 30 minutes and the message dindn't show up.

 

[Paul Higg]

Can you reset the system by jumping and then using the trip monitor buttons, then starting it up or driving it then jumping it again and see if you have any active DTC's?

 

[Enzo]

Excuse my ignorance, but what is a DTC?

 

[Paul Higg]

Diagnostic trouble code. Look in your FSM, it will tell you how to place a jumper wire to ground out two pins to enable you to see codes on the speedo. Write down any codes. Any code with a C preceding it is current, any with an H is history. The FSM will tell you how to clear the codes using the buttons on the trip monitor or just disconnect the battery to erase all codes. Then drive it a little and jump the OBD plug and look for any codes.

 

[jmccloud]

SYS light

Many forum users report that the SYS light results from a bad or weak battery (among other problems).
My '95 SYS light would occasionally blink under hard acceleration. One day while cleaning the interior with the doors open, hatch up, etc., the battery discharged so much it couldn't start the car. The interior lights were on for only 20-25 minutes.
New battery, no more SYS light.
Can you have your battery load tested? Or if it's old, just replace it.
To replace it, remove the driver's side panel behind the front wheel. Torx screws in the wheel well and 10mm (I think) bolts at the bottom. The bottom bolts require a thin wrench and do not have to come all the way out as they are in slots.
The battery ground wire connection at the frame should be cleaned up too.
Hope this helps and good luck.

 

[Enzo]

My battery was replaced few months ago. I will try to get the codes as Paul intructed, but anyway on today's drive there was no message.
Thank you.

 

[Paul Higg]

There may be stored codes. If you need help in retrieving them let me know. I love to troubleshoot these cars.

Paul

 

[Enzo]

Hi Paul. I retrieved the codes. Only history codes: H 32, H34, H36 and H 38. I hope that SYS doesn't flash again.

 

[Paul Higg]

I will get back to you soon.

Paul

 

[Paul Higg]

I assume it is the CCM giving you these codes. So here is what they mean.

32 - Will set when the CCM senses all low samples on the LCD data circuit when they should be high during CCM power-up testing. Sets a SYS light. Short & sweet - This is a nasty one as you have to remove the instrument panel (need an act of Congress for this) and use an adapter and a volt meter.

34 - Data clock circuit (circuit open or shorted to ground) resolvs the same as above.

36 - Data strobe circuit (circuit open or shorted to ground) again, same as above.

38 - M clock circuit (circuit open or shorted to ground) same resolution as above.

It looks like you may have a problem in your instrument panel.

Are you by any chance seeing either blanking of any part of your LCD indications on your speedometer? Or maybe freezing of digits? Or perhaps some part of the indication will be bright while others will be dim?

You have one of four things:

1) A short in your wiring harness leading to the instrument panel.
2) An open in your wiring harness leading to the instrument panel.
3) A loose or corroded connector on your instrument panel.
4) A bad instrument cluster.

Keep us posted.

Regards,

Paul

 

[Paul Higg]

Remember, I have a 94 so your codes per the FSM may be different but I doubt it. Look in chapter 8D for the codes and what they mean.

 

[vee93]

Once u replace the battery, all codes stored will disappear. Are you having any problems with the passive key system? If yes, then the SYS light will blink and the SECURITY light will be on at the same time.
Also, get yourself a set of factory service manuals if you don't already have them. Biiiig help if you're a diy-er. Good luck!!!

 

[Paul Higg]

Enzo, how did you make out with resetting the diagnostic system? Did you reset the codes per the FSM or disconnect the battery? Still having a SYS light?

 

[Enzo]

Hi. Sorry taking so long to be back. Paul the codes are the same on my FSM. Today I reset the codes per the FSM. Drove for almost one hour and no message. I don't see anything wrong on my panel indications. Hope the thing fixed by itself. Who knows. If I have to fix it, will be big trouble since I don't have technical skills to do that and it is hard to find a Vette mechanic here. There are very few Vettes in the country. Thanks everybody for the big help.