SYS code on dash... WT heck
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SYS code on dash... WT heck
1993 Vette, new battery, alternator shows 14.2 output via voltmeter at alternator and at battery. Dash meter shows 14.1 at idle, out of gear.
Car uses battery tender daily, and this is the first time I drove it in a month.
ANy ideas? Runs fine..
Car uses battery tender daily, and this is the first time I drove it in a month.
ANy ideas? Runs fine..
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Then the Tender again. What brand Tender? Model?
Last edited by WVZR-1; Jan 19, 2016 at 04:20 PM.
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Voltage reads 12.98 now. Not running. Cars off
Last edited by krackenvette; Jan 19, 2016 at 04:29 PM.
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I believe that an extended stay on a Tender can cause precisely what you see. The system I believe is accustomed to a conventional charge to keep the battery at charge and the very slow 1.25 or 1.5 SLOW charge likely tricks the system into a value it's not accustomed to seeing and it triggers the SYS as an ERROR.
To avoid maybe taking the battery out turn on the lights for 5 - 7 minutes with car NOT RUNNING, turn lights off and crank the car. If it doesn't start it's time for a battery(warranty if new or recent) for sure. If it cranks and runs check the alternator output then, react as you see fit.
Last edited by WVZR-1; Jan 19, 2016 at 05:33 PM.
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But you didn't disconnect the battery cable(s) to let it rest. Right?
I believe that an extended stay on a Tender can cause precisely what you see. The system I believe is accustomed to a conventional charge to keep the battery at charge and the very slow 1.25 or 1.5 SLOW charge likely tricks the system into a value it's not accustomed to seeing and it triggers the SYS as an ERROR.
To avoid maybe taking the battery out turn on the lights for 5 - 7 minutes with car NOT RUNNING, turn lights off and crank the car. If it doesn't start it's time for a battery(warranty if new or recent) for sure. If it cranks and runs check the alternator output then, react as you see fit.
I believe that an extended stay on a Tender can cause precisely what you see. The system I believe is accustomed to a conventional charge to keep the battery at charge and the very slow 1.25 or 1.5 SLOW charge likely tricks the system into a value it's not accustomed to seeing and it triggers the SYS as an ERROR.
To avoid maybe taking the battery out turn on the lights for 5 - 7 minutes with car NOT RUNNING, turn lights off and crank the car. If it doesn't start it's time for a battery(warranty if new or recent) for sure. If it cranks and runs check the alternator output then, react as you see fit.
Battery is maybe 8 months old.
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Bad/low battery. My 96 needed the 'tender' on it or it would get low after a month or so and not start. Gave the "SYS" code when it was jumped off which went away when the battery was charged up again.
My 93 sits for a month or more; battery stays up just fine with no tender; no "SYS" codes.
Good luck.
walt z.
My 93 sits for a month or more; battery stays up just fine with no tender; no "SYS" codes.
Good luck.
walt z.
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Had alternator tested at parts store. Passed.
Drop tested battery via watching voltmeter during crankinh. Never went below 10 volts.
Did find blown LH crtsy 20 amp fuse. Think that could cause sys flashing?
Drop tested battery via watching voltmeter during crankinh. Never went below 10 volts.
Did find blown LH crtsy 20 amp fuse. Think that could cause sys flashing?
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let us know it might take a bit to reset if it does not reset I would disconnect the battery to try to reset. 
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I would doubt the CTSY fuse was a fix but then it is "fixed" (assumed). I'd think that while you had the alternator off (with battery disconnected) the CCM cycled and reset. The CTSY I'd think coincidental. Time will tell!!
Last edited by WVZR-1; Jan 20, 2016 at 11:05 AM.
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Blown fuse is strange though.
I loaded the car too with defroster on, rear defrost and lights in gear. Didnt go below 14.1 after sitti ng for about 5 minutes. My 396LT1 does idld a little higher at 850.