What is the SYS light
Thread Starter
Le Mans Master
Joined: Feb 2001
Posts: 6,398
Likes: 1
From: Loveland Co
Cruise-In III Veteran
What is the SYS light
what is the light on the dash cluster that flashes SYS three times for? it did it the other day when my battery was not charging, i changed the battery out and it went away
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: What is the SYS light (No Ordinary 91)
It indicates that the Engine Management Computer (ECM) has detected a problem condition with a sensor, including battery voltage.
If the SYS light comes on when the engine is running the ECM usually sets a code indicating the trouble.
Read the tech notes on how to pull the codes and if one is set disconnect the small power lead to the ECM near the battery for about a minute to clear it.
If the SYS light comes on when the engine is running the ECM usually sets a code indicating the trouble.
Read the tech notes on how to pull the codes and if one is set disconnect the small power lead to the ECM near the battery for about a minute to clear it.
Thread Starter
Le Mans Master
Joined: Feb 2001
Posts: 6,398
Likes: 1
From: Loveland Co
Cruise-In III Veteran
Re: What is the SYS light (65Z01)
okay well the battery barely would hold enough charge to start the car back up, and actually didn't register on the meter when i turned the engine off when i got home, so that is probably what it was
LS/MFT
Joined: Jun 2000
Posts: 5,874
Likes: 0
From: Cary IL
St. Jude Donor '09-'10-'11-'12
Re: What is the SYS light (No Ordinary 91)
Is this happening to EVERYONE? :eek: Check out my post at http://forums.corvetteforum.com/zerothread?id=226547 .
:blueangel: In deference to 65Z01, a "SYS" display means the CCM (Central Control Module) -- the "main brain" under the dash -- has set a code. When the ECM -- the computer in the engine compartment above the brake booster ('90 and later, also under the right side of dash, earlier) -- reads a fault your SES (Service Engine Soon) light will flash. Read codes for both by following instructions at the linked post.
:blueangel: In deference to 65Z01, a "SYS" display means the CCM (Central Control Module) -- the "main brain" under the dash -- has set a code. When the ECM -- the computer in the engine compartment above the brake booster ('90 and later, also under the right side of dash, earlier) -- reads a fault your SES (Service Engine Soon) light will flash. Read codes for both by following instructions at the linked post.
Drifting
Joined: May 1999
Posts: 1,478
Likes: 3
From: Sacramento, CA Money can't buy happiness - but it's more comfortable to cry in a Corvette than a Yugo.
Re: What is the SYS light (Vette73)
Vette73,
What you sare saying to "No Ordinary 91" is correct, but 65Z01 is also correct for 89 and earlier vettes. The 89 and earlier vettes (like his 88 and mine) do not have a CCM. According to the 88 GM Factory Manual it is an "electronic engine control module (ECM)". The CCM was incorporated in 90 and later vettes. It was at that time that the termanology for ECM was changed to PCM (powertrain control module).
What you sare saying to "No Ordinary 91" is correct, but 65Z01 is also correct for 89 and earlier vettes. The 89 and earlier vettes (like his 88 and mine) do not have a CCM. According to the 88 GM Factory Manual it is an "electronic engine control module (ECM)". The CCM was incorporated in 90 and later vettes. It was at that time that the termanology for ECM was changed to PCM (powertrain control module).
Le Mans Master
Joined: Aug 2000
Posts: 6,715
Likes: 76
From: Bloomington IL
Re: What is the SYS light (No Ordinary 91)
The flashing SYS seems to be happening quite a bit here. I did a quick search on the subject and found it was because my battery was low on juice. Charged it up and the SYS is no more.
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