Hi,
Can somebody tell me how to read this code? I know that there is a pin that you can ground and the car is supposed to be able to give you the numerical value of these codes. The car is a '91 coupe. This just came on last night, but there was no difference in the way the car drove. I just installed a new radio and removed the amplifier box, if that makes a difference? Also, just prior to going for the drive my battery was low and I had to charge it. But then it started and drove just fine for about 12 miles before the code came on.
Any help would be appreciated.
Glen

 

Glen, the SYS falshing means the CCM has detected a problem in the electrical system. It kind of works like check engine light for the engine computer, but for the electrical systems. Since you've just changed radios, I'd put a really big bet on the CCM giving codes 72 and 74. This is because the dimmer system in aftermarket radios is not completely compatible with the cars dimmer system. Here's the TSB for you http://www.corvetteforum.net/c4/dave8476/index4.shtml and here the simplified version from Craig Marcho a bit easier to follow:
If "SYS" is displayed in the LCD section of the instrument panel cluster after the customer installs a new stereo, he will need to do the following:

1. Buy (2) 1 kilo-ohm 1/2 Watt resistors. [Radio Shack part # 271-023. They sell them as a 2-pack for 29 cents.]
2. Disconnect the negative battery cable.
3. Remove the receiver.
4. Connect one end of both resistors to ignition power. (Yellow wire in the car.)
5. Connect the other end of one resistor to the purple/white wire in the car.
6. Connect the other end of the second resistor to the grey/black wire in the car.
7. Cover all connections and completely cover the resistors.
8. Reconnect the negative battery cable.

:steering:

 

Maybe this link?
http://www.c4vettes.com/ecm.htm

 

Great answers for checking which codes are being triggered, and what to do about the radio if this is the proble (sure sounds like it!) Regarding the resistors, are they run in Parallel with the wires, or in series? In other words, do I cut the wires and run the power from the yellow wire through the resistors to the Gray/White and Purple/Black wires? Or do I strip a small bit of insulation off the yellow, Purple/Black, & Gray/White wire and solder the resistors from the Yellow to the other two wires, while leaving all the other unions intact? Thank you for the help!
Glen

 

Maybe this link?
http://www.c4vettes.com/ecm.htm

I have been looking for a link like this for a long time-thanks
:thumbs:

Rocky
87 vert

 

I've had that code since I owned my vette (3 years) because of radio. No problem with anything else.

 

:thumbs: