Norcalzosix

I have a 2002 Z06 and recently (at start up only) I get a quick code of ALL Asterisks on my welcome screen . The car sounds like it chokes/struggles for a real quick second and then it appears to be fine. Have any of you had or known of this issue? Trying to figure out what it is without having to take it into the shop. Anything you can provide me with would be GREATLY appreciated!

lucky131969

codes?

Bill Curlee

CODES??

BC

READING YOUR Engine Diagnostic Codes



The Diagnostic Display Mode is entered with the following procedure:
1) Turn on the ignition but don't start the engine.
2) Press the RESET button to turn off any warning messages. (i.e. door open, trunk open ect)
3) Press and hold OPTIONS
4) While holding OPTIONS, press FUEL four times within a 10-second period.


Initially, on-board diagnostics go into an Automatic Mode which shows diagnostic codes in a pre-set sequence: PCM - TCS - RTD - BCM - IPC - RADIO - HVAC - LDCM - RDCM - SCM - RFA. All codes will be displayed for each. ( i.e. PCM = 4 codes) If none are present in a given module, you will see No More Codes on the display.
There are two kinds of diagnostic codes, Current and History designated with a letter suffix, “C” or “H”. A current C code indicates a malfunction is present and active in the module displaying data. A history code indicates a problem existed sometime in the last 40 or 50 ignition cycles. When not accompanied by a current code of the same number, it's potential evidence of a previous problem, now resolved, that was not removed by clearing the codes.
More likely it's an indication of an intermittent malfunction.
Intermittent codes are the most challenging of the diagnostics. An intermittent code may have happened once, may have happened more than once but is inconsistent or may be happening on a regular basis but not at the time the codes are displayed. History codes can also be caused by a current malfunction in a system that is not operating at the time codes are displayed. An example is the rear window defogger which doesn't operate until the Body Control Module detects engine rpm. For history codes set by a module that does not operate with the key on and engine off, a special diagnostic tool called a Scan Tester is necessary to properly diagnose the malfunction.
Once the system has displayed all modules, it goes into the manual mode which allows selection of each module using combinations of Driver Information Center buttons. Manual mode can also be entered during the automatic sequence by pressing any button except English/Metric (E/M). Once the display shows Manual Diagnostics, select a module by pressing the OPTIONS button to go forward or the TRIP button to go back. Once a module is selected, a code is displayed, and if more than one are present; press GAGES to go forward or FUEL to go back.
To exit the diagnostic mode at any time, press E/M. If you want to erase codes in a given module, press and hold the RESET button To reset the codes once in manual mode, press and hold RESET until it displays NO CODES Press OPTIONS to go to the next module. Repeat the steps until you have reset the codes in all the computer modules.
NOTE!! Only reset the codes IF you want to - it is NOT necessary to do this. Clearing a code does not repair a problem. You are simply erasing the evidence of it in the module's memory. If you clear the code/s, and extinguish the Check Engine Light, your emissions status ready will NOT allow you to pass an emissions test until you have completed the required driving cycles.
Once you have the codes, the next question is: What to do with the information?
First, consult the factory service manual. Any serious C5 Do-It-Yourself owner should invest in the Corvette Service Manual of the appropriate model year. The Service Manual is really a requirement if you want to understand and work on your C5. You can GOOGLE the DTC and also find information on it.




Here is very good site that explains the DTCs:


http://www.corvette-web-central.com/C5DTCcode.html


http://www.obd-codes.com/trouble_cod...d-ii-codes.php



Make sure to include the H or C suffix!!

Norcalzosix

The only code without an H prefix is the following

C1214 H/C Solenoid Valve Relay Contact or Coil Circuit Open

Does this also sound like a battery issue? One more thing I noticed. On my HUD it's always displaying OIL when I start my car instead of my GAS level. Is this is sign there is something wrong with my oil? Never had that happen before.

lucky131969

post ALL codes...

Bill Curlee

YUP!! Thats a direct indication of a "WEAK" battery. When you crank your car, the starter draws around 250 - 300 amps (depending on temperature, engine compression etc..... could be more or a little less. ) When current draw is HIGH, voltage goes LOW. If your battery is old or low on charge and cant support the demand of the starter motor, your actual battery voltage output may drop as low as 7-8 VDC. The actual time period that the voltage is that low is most likely measured in milliseconds but its long enough to cause module to have issues and shut down.

I know,,,,,,,,,,,,,,,,,,,,,,,,your thinking, how can that be? My car starts every time I ask it to! Yea, it starts because the current is there to drive the starter. Your battery has more than enough current to drive the starter. Should be 550 amps.

When the battery voltage output drops LOW, (below 8 VDC) the modules that have a memory shuts down (while the voltage is below the shut down threshold) and defaults to the factory preset settings.

Take your battery out and have it fully tested. Have them do a load test and reserve capacity test. I bet ya it will fail. Have you ever played the stereo for an extended period of time (with the engine OFF) and then when you went to start the engine the starter seemed to drag?

BC

Norcalzosix

BC thanks for the heads up. I also had that code that says "Low System Voltage" or whatever it is but it did have an "H" next to it. I will definitely have the battery tested. Makes sense!

I appreicate the love

Bill Curlee

IF,,,,,,,,,,,,,,,,,,,,,,,,your battery checks out fine,,,,,I have one more thing for you to investigate. Give me the results of your battery check when it gets completed.

Make sure that you clean the terminals and cables ends before you reconnect it back up. The terminals need to be properly torqued to the battery. 97-2003 C5 need to be torqued to 11 ft/lbs for proper connection.

BC

Alaskanpilot

I don't think that means anything. I'm going off memory here since I rarely switch that display, but you can switch the side of your HUD to display either gas, oil pressure, or water temp (I believe) by holding the PAGE button (again, I believe... someone correct me if I'm wrong). If I remember, it cycles between the various display configurations, which also include yay or nay on the rpm bar.

If your HUD is displaying the oil bar instead of the gas bar, all it means is that you accidentally toggled the display mode.

Bill Curlee

If you set all the operator changable settings to your perfered positions and set the MEMORY Function to remember them, they should stay set each time you FOB the car or press the memory button.

IF, the memory settings reset to the factory settings on their own, the IPC or SEAT Module lost its power some how.

BC