99 key fob problems
Thread Starter
Intermediate
Joined: Oct 2006
Posts: 27
Likes: 0
From: Abilene Texas
99 key fob problems
My key fob seems to have a mind of its own...Ill program it to the car and it recognizes it and says its learned and works...then i got away from the car and then come back to unlock the car and the fob will not do anything...I have replaced the battery in the fob...and it still wont work....any suggestions?
Thanks
Thanks
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
Your C5 has a built in code reader:
This is the absolute best C5 Diagnostic Trouble Code (DTC) web site!!!
http://www.corvettedoctor.com/Code_Main.html
http://www.corvettedoctor.com/index.html
www.corvettedoctor.com
Go to “technical data base” and then to “Corvette ECM Computer Codes”. Then select your year car. Read the instructions and then scroll down to the "READ MORE" window to view the code definitions.\
Here is another very good site:
http://www.obd-codes.com/trouble_cod...d-ii-codes.php
Make sure to include the H or C suffix!!
Read and post the DTC's Then CLEAR ALL of them. When the FOB malfunctions, read the codes again to see what if any codes relate to the RDF or BCM.
BC
This is the absolute best C5 Diagnostic Trouble Code (DTC) web site!!!
http://www.corvettedoctor.com/Code_Main.html
http://www.corvettedoctor.com/index.html
www.corvettedoctor.com
Go to “technical data base” and then to “Corvette ECM Computer Codes”. Then select your year car. Read the instructions and then scroll down to the "READ MORE" window to view the code definitions.\
Here is another very good site:
http://www.obd-codes.com/trouble_cod...d-ii-codes.php
Make sure to include the H or C suffix!!
Read and post the DTC's Then CLEAR ALL of them. When the FOB malfunctions, read the codes again to see what if any codes relate to the RDF or BCM.
BC
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
FOBs do go bad. If you had two, you could see if the other one worked properly. Your car origionaly came with TWO. You can program up to THREE!
Are you preforming the Re-sync or Re program when the FOB malfunctions???
A weak or low on charge 12 VDC main battery can cause the same thing to happen. When you start the engine when its cold the starter draws the most current. As current goes UP, voltage goes DOWN. I have seen weak batteries allow the 12 VDC B+ voltage to drop as low as 9 VDC and the car will still start and run normaly. This causes the modules to shut down during the low voltage time period. When the car starts the modules throw the U series history codes.
A sign that this is possibly happening will be a ton of U series codes and or NO Comms codes.
Others are fuel mileage resets, you loose all your memory presets.
BC
Are you preforming the Re-sync or Re program when the FOB malfunctions???
A weak or low on charge 12 VDC main battery can cause the same thing to happen. When you start the engine when its cold the starter draws the most current. As current goes UP, voltage goes DOWN. I have seen weak batteries allow the 12 VDC B+ voltage to drop as low as 9 VDC and the car will still start and run normaly. This causes the modules to shut down during the low voltage time period. When the car starts the modules throw the U series history codes.
A sign that this is possibly happening will be a ton of U series codes and or NO Comms codes.
Others are fuel mileage resets, you loose all your memory presets.
BC
Melting Slicks
Joined: Dec 2000
Posts: 2,118
Likes: 2
Heres another option..... I had continuous problems with the factory '99 FOB. I finally gave up on making it woirk. I installed the Clifford system. Its been in the car for 4 years and it works flawlessly. The factory units are a continous problem for alot of C5 owners. Its not cheap, but if you get as frustrated as I did with the factory POS, then the Clifford is the way to go. 
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
I have NEVER had to reprogram the one in my 02 ZO6. It just keeps on working! Once I figured out what was causing my 98 FOB to die, that one worked perfect too! Don't throw the towel in on the OEM FOB until you do some research and maintenance.
If you need to get another FOB, it isn't all that much and will last a long time. Look on E-bay. Try to find new ones.
If you find someone in your area with another C5 of the same year/FOB design ( there are three designs and there NOT compatible) , see if you can program one of his FOBs to your car and see if that fixes the problem.
97-2000
2001
2002-2004
If you need to get another FOB, it isn't all that much and will last a long time. Look on E-bay. Try to find new ones.
If you find someone in your area with another C5 of the same year/FOB design ( there are three designs and there NOT compatible) , see if you can program one of his FOBs to your car and see if that fixes the problem.
97-2000
2001
2002-2004
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Safety Car
Joined: Jul 2000
Posts: 3,596
Likes: 37
From: Orange County CA
My key fob seems to have a mind of its own...Ill program it to the car and it recognizes it and says its learned and works...then i got away from the car and then come back to unlock the car and the fob will not do anything...I have replaced the battery in the fob...and it still wont work....any suggestions?
Thanks
Thanks
