strange error message "SYS"
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Joined: Jul 2003
Posts: 54
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From: Saugus Ca
strange error message "SYS"
recently my c4 has been giving me a strange error message where it usually displays my range, avg mpg, and current mpg.......does anyone know what it means ? it flashes on and off and says "SYS" thanks for your help
Instructor
Joined: Jun 2003
Posts: 101
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From: West TX
Re: strange error message "SYS" (nottheliving)
I noticed that on my display last week after my oil change. It came on after the car was started a few times, but I haven't seen it since. I too would like to know what it meant.
Racer
Joined: Nov 2000
Posts: 415
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From: mauriceville texas
Re: strange error message "SYS" (nottheliving)
I first bought a factory service manual. I spent about 2 1/2 months going step by step and it was driving me crazy. Finally i called the chevy dealer to see what they did and the answer i got was "start changing parts in the order of the manual and you will sooner or later track it down." That may be fine for a chevy dealer who has access to parts he can put back in the box, but for me it is pretty expensive. After about 800 dollars in modules, switches, etc, i was down to the ecm. Fixed the problem. Up side to this is all the under hood electronics are new. This was a serious pita. robert
Safety Car
Joined: Aug 2002
Posts: 3,842
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From: SANTA CRUZ CA
Melting Slicks
Joined: Aug 2000
Posts: 2,009
Likes: 1
From: Springfield MO
Re: strange error message "SYS" (nottheliving)
My 90 will do this too. I have two different chips that I run in my car. One my buddy made and one from fastchip. The one from Fastchip won't flash the sys but the one my buddy made will. It is definately ecm related. Does it by chance have an aftermarket chip in it. By the way.....it only happends periodically right??
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Race Director
Joined: Jun 2001
Posts: 10,956
Likes: 680
From: Marlboro country MA
Re: strange error message "SYS" (AS84)
Check your battery first. My 92 did this whenever I started it up with a nearly discharged battery. Replacing the battery also ended teh flashing SYS.
Melting Slicks
Joined: Jul 1999
Posts: 2,875
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From: Olive Branch (Memphis suburb) MS
Cruise-In II Veteran
Re: strange error message "SYS" (nottheliving)
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. I"ll try and remember to post the procedure for pulling the CCM codes when I get home from work. :steering:
Melting Slicks
Joined: Jul 1999
Posts: 2,875
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From: Olive Branch (Memphis suburb) MS
Cruise-In II Veteran
Re: strange error message "SYS" (Ramrod92)
Ok, this is long. First ground pin G of the ALDL connector. You can do this by using the paper clip from G to A (which is the ground) 
Turn the key on, but do not start. The CCM will display any fault codes in sequence using the digital speedometer area. In smaller numbers just below these readouts it will also display the module for which they apply. The CCM is module 1, the ECM is module 4, the ABS/ASR EBCM is module 9. Post which fault codes are present and we'll try to explain them. If you plan on doing much work on your car I would strongly suggest you obtain a copy of the Helms service manual for your model. 
http://www.helminc.com/helm/product2...7681ACABCHE7XD
Turn the key on, but do not start. The CCM will display any fault codes in sequence using the digital speedometer area. In smaller numbers just below these readouts it will also display the module for which they apply. The CCM is module 1, the ECM is module 4, the ABS/ASR EBCM is module 9. Post which fault codes are present and we'll try to explain them. If you plan on doing much work on your car I would strongly suggest you obtain a copy of the Helms service manual for your model. http://www.helminc.com/helm/product2...7681ACABCHE7XD
Melting Slicks
Joined: Apr 2003
Posts: 2,150
Likes: 6
From: NS
Re: strange error message "SYS" (Ramrod92)
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. I"ll try and remember to post the procedure for pulling the CCM codes when I get home from work. :steering:
:cheers:
Team Owner
Joined: Aug 2000
Posts: 31,950
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From: Columbus OH
Elite Member
Cruise-In III Veteran
St. Jude Donor '09
Re: strange error message "SYS" (MTVette)
Check your battery first. My 92 did this whenever I started it up with a nearly discharged battery. Replacing the battery also ended teh flashing SYS.
Melting Slicks
Joined: Jan 2000
Posts: 3,418
Likes: 1
From: NW Chicago Suburbs
Re: strange error message "SYS"
Check your battery first.
Eric
