1998 C5 loses its memory on the DIC
Thread Starter
Intermediate
Joined: Nov 2007
Posts: 34
Likes: 3
1998 C5 loses its memory on the DIC
In the past I have had intermittent problems with the fuel gauge showing empty when the tank is full. I was advised that I needed to add Techron, which I have done and that seems to keep that issue under control, but lately I have developed some additional issues. The car has almost 110,000 miles on it and lately it doesn't seem to want to retain information on the DIC - i.e. average fuel consumption goes to 0, trip computer goes to 0 and the DIC displays the actual mileage on the car. I've also, on occasion, gotten the "Pull key and wait 10 seconds" message. I've spoken with some other owners who have told me that I might have a bad fuel sending unit, others the ECM or BCM and still others that I might be having issues with bad grounds. I live in Wyoming and that limits the amount of driving time that I get because of weather and also limits my knowledge of what makes my C5 tick. If anyone has some ideas that I might try or steer me in the proper direction, I would appreciate it.
Le Mans Master
Joined: Sep 2003
Posts: 8,812
Likes: 2,029
From: eastern NC
It really sounds as if your battery voltage is low. I would perform a battery voltage test over a 24 hour period of time.
I would start by disconnecting the underhood light and waiting about 20 minutes to take a direct battery voltage reading. Without opening any doors or activating any systems check the voltage about every couple of hours until you go to bed and then the first thing in the morning.
If the battery is good, the voltage shouldn't drop more than about a volt. If it drops to below 11 volts, that could explain the issues you're experiencing. If the voltage remains above 12 volts, I would start checking some of the grounds on your car.
Good luck... GUSTO
I would start by disconnecting the underhood light and waiting about 20 minutes to take a direct battery voltage reading. Without opening any doors or activating any systems check the voltage about every couple of hours until you go to bed and then the first thing in the morning.
If the battery is good, the voltage shouldn't drop more than about a volt. If it drops to below 11 volts, that could explain the issues you're experiencing. If the voltage remains above 12 volts, I would start checking some of the grounds on your car.
Good luck... GUSTO
Melting Slicks
Joined: Jul 2004
Posts: 3,294
Likes: 482
From: Brea CA
If the battery is over 3 years old replace it. These are the symptoms of a battery that does not have enough capacity to keep all the IPC preferences while cranking.
While replacing the battery have the connection inspected for corrosion not only at the terminals but at the starter terminals. Also look for signs of battery acid spills in the battery tray. If there were any signs of this pull the battery tray and inspect the wiring harness under it for damage.
Gary
While replacing the battery have the connection inspected for corrosion not only at the terminals but at the starter terminals. Also look for signs of battery acid spills in the battery tray. If there were any signs of this pull the battery tray and inspect the wiring harness under it for damage.
Gary
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
100% ALSO!! 
Your battery voltage is dropping too low when you first crank the engine and all the cars MEMORY erases its self and goes back to factory default settings.
You will also find that the cars emissions reset to the NOT READY state and will require the drive cycles to get them to the READY STATE.
Bill
