problem with sys flashing and code 12
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 3,019
Likes: 0
From: down that one road next to that big tree
problem with sys flashing and code 12
what in the world is up with the ECU? i have a slew of code 12's and sys flashes where my ist/avg is on the cluster, sys flashes every few seconds, i have a continious service engine soon going on also. here's the damdest part, when i'm up to temp and drive around it will go away, but EVERY morning it comes back and the car won't run right for awhile...help this one even has me stumped. one more note i can only pull codes when it's not in the flashing sys perminate SES mode. the SES will not flash with a code reader in at this time, it has to be running right before i can pull codes.
[Modified by gtsyellow, 3:34 PM 9/21/2002]
[Modified by gtsyellow, 3:34 PM 9/21/2002]
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 3,019
Likes: 0
From: down that one road next to that big tree
Re: (scorp508)
scorp hit my best guess right on the head, i have one of ed wrights piggy back chips. my stock chip plugs into that and then i incert it in the ECU, problem is my stock chip hits on a chip in the ECU. i've made it work with some dielectric greese around the pins and a good solid push but i think i'm going to have ole ed do a prom burn on my stock chip. these piggy backs suck, the seating is very very picky.
Burning Brakes
Joined: Jun 2000
Posts: 1,148
Likes: 48
Re: problem with sys flashing and code 12 (gtsyellow)
SYS light= battery low charge
Code 12=is normal. When using the "flash code" system, a code 12 will be flashed to let you know the PCM is in diagnostic mode.
A bad battery can cause a lot of strange problems.
When my battery went on me, all my dash lights would dim, get bright and then dim again. My idiot lights would flash on and off and the car would run like crap. It's like I was in the Bermuda triangle or something and yet all it was was a bad cell in my battery. :crazy:
I'd check there first.
Code 12=is normal. When using the "flash code" system, a code 12 will be flashed to let you know the PCM is in diagnostic mode.
A bad battery can cause a lot of strange problems.
When my battery went on me, all my dash lights would dim, get bright and then dim again. My idiot lights would flash on and off and the car would run like crap. It's like I was in the Bermuda triangle or something and yet all it was was a bad cell in my battery. :crazy:
I'd check there first.
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 3,019
Likes: 0
From: down that one road next to that big tree
Re: problem with sys flashing and code 12 (Vette Threat)
i'll leave it on the charger tonight & see what happens in the morning, if it's all good i'll be buying a battery this afternoon, i've noticed the car is cranking rather slow at times.
[Modified by gtsyellow, 2:24 AM 9/22/2002]
[Modified by gtsyellow, 2:24 AM 9/22/2002]
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Verdad Gallardo
Safety Car
Joined: Mar 2000
Posts: 3,620
Likes: 2
From: Hillsboro OR
Re: problem with sys flashing and code 12 (Vette Threat)
When my battery went on me, all my dash lights would dim, get bright and then dim again. My idiot lights would flash on and off and the car would run like crap. It's like I was in the Bermuda triangle or something and yet all it was was a bad cell in my battery.
Another sign of a shorted cell or cells is when you try to jump start it and the jumper cables start melting when you connect it to a good battery. :rolleyes:
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 3,019
Likes: 0
From: down that one road next to that big tree
Re: problem with sys flashing and code 12 (AquaMetallic94LT1)
oddly enough when i smeared dielectric greese on my prom yesterday & really seated it the problem went away. the car had been running for almost 20min in limp mode however and the alternator would have picked up by then. car has been charging all night i'm going to go take a drive, & probably pick up another battery to be safe, this one has been drained dead like 3 times and it's 2yrs old.
Burning Brakes
Joined: Feb 2000
Posts: 824
Likes: 2
From: Camden SC
Re: problem with sys flashing and code 12 (gtsyellow)
My vote is to start with the battery and see what problems remain.
In low voltage conditions, the ECM will adjust injector on times for reduced voltage. It extends injector on time because it assumes the injector response times have slowed. Probably that darned volts/amps/resistance thing again. This may cause the engine to run poorly.
Good luck.
dlmeyers 90 coupe zf6 3 speed shocks
In low voltage conditions, the ECM will adjust injector on times for reduced voltage. It extends injector on time because it assumes the injector response times have slowed. Probably that darned volts/amps/resistance thing again. This may cause the engine to run poorly.
Good luck.
dlmeyers 90 coupe zf6 3 speed shocks
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 3,019
Likes: 0
From: down that one road next to that big tree
Re: problem with sys flashing and code 12 (dlmeyers)
let the car charge all night, not a SINGLE problem, well besides my oil psi and temp sending unit, this engine has insane oil psi and will burry the guage under WOT not suprising i'm pissing oil like a old man. next i'm going to try permetex thread sealer and fuel proof teflon tape.
Burning Brakes
Joined: Aug 2002
Posts: 848
Likes: 0
From: Houston TX
Re: problem with sys flashing and code 12 (gtsyellow)
Yep, I got the "SYS" flashing when my battery was low because I'd been working inside the car all day, and the interior lights had drained the battery. After about 1/2 hour of driving, it went away.
