dtorc4

I test drove a 94 w/ 37k miles today. I kept on flashin a "sys" indicator on the digital readout where the gas mileage appears. What does "sys" mean? Is it bad? The car ran really well. :confused: :cheers:

Ramrod92

Darrin, the SYS indicates the CCM (not the ECM, engine control module) has detected a fault. Two of the most common reasons are the CCM has seen the ignition voltage out of range(usaully just a battery going) or the radio head unit has been changed to an aftermarket unit that has a different resistance in the backlight dimmer circuit which the CCM takes to be an error(which can be fixed easily).There are a few other things that can set the SYS, but they don't effect the engine. :crazy:


[Modified by Ramrod92, 11:49 PM 11/9/2001]

dtorc4

Thanks man, I thought it was something more serious than that. And yes, the radio has been replaced by some POS Jbl cd player. :cheers:

Ramrod92

Check this out http://forums.corvetteforum.com/zerothread?id=139694 :cheers:

dtorc4

Thank you. :yesnod:

jay17

Mine does the same thing. It has a Kenwood deck, so I'm guessing that's what it is.

ZBRA

Any time the head unit has been changed, this will happen. You have to wire in two resistors in the back to make it stop.

jpee

I installed a manual fan switch in my car, (96) It completely bypasses the computer, it's hot wired from the battery, to new separate solenoids..so I can run just the fans while the ignition is off.

Today at Englishtown I ran the fan more than usual, & I also noticed a SYS when I turned on the ignition...

Do you think this was because it sensed the battery had a big drain ? Even though the fan switch I have is not running through the computer..

GlockLT4

yep.. I've had the SYS both ways. First because of the aftermarket radio.. I got that fixed with 2 resistors.. then next I got it a few months later because my battery was dying. No more SYS .. for now

jay17

Could someone tell me how to fix the head unit problem?

OcalaGuy

Can you email me at ocalaguy@aol.com on how you wired your fans. I want to do the same thing on my '96. I can not get my fans to come on without turning on the ac fan. I hate that with the top down. I have had the fans worked on 3 times now and they still don't work.

Thanks,

Jim

Ramrod92

Jay, check the link I posted. :cheers:

Ramrod92

John, that is probably what happened. When the battery voltage drops below a set number the sys will set. I'm not up on the OBDII stuff, so I'm not as sure about how it works, but on the some of the OBDI cars a code 28 will set when a manual fan switch is used. I think Chris (Vette92) had this happen. :crazy:

jpee

Ransome.. thanks, I have a new battery, my old one was ok, but being almost 5 yrs old I thought it best to replace it..

Next week is our last week of racing this year, but now that I know that, I'll just be more aware of how much I run the fans with the motor off..

BrianCunningham

Sounds like your problem is with the stereo
BTW thanks for the heads up ( no pun inteneded :D )

a Manual Fan Switch will do it to.
My Mid-America kit actually said do in the instructions.

But I also needed to replace my battery, had to have it jump started twice! :mad

I put an Optima in it and it's been fine since ( need knock on wood icon )

Nathan Plemons

Been there, had the problem when I replaced my stereo. You CAN fix the problem with a 12v LED as well, but I don't remember off the top of my head which wires you connect it to.