SYS and no fault found
Thread Starter
Burning Brakes
Joined: Jan 2010
Posts: 967
Likes: 109
From: Europe, Germany
SYS and no fault found
Hi everyone,
I have a 91 Convertible and running out of ideas what else to do
Symptome
- SYS is flashing regulary while driving
- Cluster is working but you cant change any of the indicators
.- as the the switches to change the indication of the cluster are not working you can not recall any failure-codes
- aircondition panel is not working because non of the switches is working (Heating is permanatly on)
Im not sure if this is different issue or caused by the same as for the SYS Flashing:
Sometimes the starter wont work : Turn Key all lights are on as regulsr , turn to start nothing changes and the starter does nothing
- meanwhile I found out , when I close the car with the grey switch in the doorpanel and open it, the starter works as regular.
I have already done :
- Batterie overnight disconnected
- changed ECM
- checked all ground connections and starter
- checked fusebox
only issue I have found is this lose connector and can not found where it should belong to
Frank
I have a 91 Convertible and running out of ideas what else to do
Symptome
- SYS is flashing regulary while driving
- Cluster is working but you cant change any of the indicators
.- as the the switches to change the indication of the cluster are not working you can not recall any failure-codes
- aircondition panel is not working because non of the switches is working (Heating is permanatly on)
Im not sure if this is different issue or caused by the same as for the SYS Flashing:
Sometimes the starter wont work : Turn Key all lights are on as regulsr , turn to start nothing changes and the starter does nothing
- meanwhile I found out , when I close the car with the grey switch in the doorpanel and open it, the starter works as regular.
I have already done :
- Batterie overnight disconnected
- changed ECM
- checked all ground connections and starter
- checked fusebox
only issue I have found is this lose connector and can not found where it should belong to
Frank
Le Mans Master
Joined: Feb 2000
Posts: 9,061
Likes: 214
From: Epping NH
Check for current draw to start with while everything is off and no lights are on in the car...this sounds like a short somewhere. Should be around .03 Amps or 30 miliamps. Pretty easy test to do with a cheap multimeter. Also where does the lose wire run back too? Does it look like it's part of a wire assembly or did someone splice it in?
Banned Loser
Joined: Aug 2009
Posts: 53,424
Likes: 250
From: They say you learn from your mistakes, I must be a genius
2017 Corvette of the Year
2016 C4 of Year Finalist
Creator of the "Original" whining and crying thread
St. Jude Donor '14-'15-'16-'17
How old is your battery? Sounds like you could have a dead cell or it's just time to replace the battery itself
Banned Loser
Joined: Aug 2009
Posts: 53,424
Likes: 250
From: They say you learn from your mistakes, I must be a genius
2017 Corvette of the Year
2016 C4 of Year Finalist
Creator of the "Original" whining and crying thread
St. Jude Donor '14-'15-'16-'17
Banned Loser
Joined: Aug 2009
Posts: 53,424
Likes: 250
From: They say you learn from your mistakes, I must be a genius
2017 Corvette of the Year
2016 C4 of Year Finalist
Creator of the "Original" whining and crying thread
St. Jude Donor '14-'15-'16-'17
I've had the SYS come up twice in the 15 years I've owned my C4, both times the battery was the culprit. Good luck 
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