Hi. My name is josh. I new to this forums thing. I am in desperate need for help. I just bought a 99 c5. And I’m having key fob programming issues. Let me start by saying that I have checked the fobs internal contact points. Battery is new. Chip board is in perfect condition. Now corrosion etc. so with that being said I’m pretty sure it’s not the fob. So I do the program with the only key fob that I have. Standing out side the car holing the lock & unlock. The horn honks to confirm. The the fob works for just a few minutes. The car locks and unlocks with the buttons. But if I just lock it few seconds later the doors unlock themselves.
And And inevitably five loses its programming. This is driving me crazy. Please help and be kind. I’m new to this. Thank you

 

Your '99 has a switch on the fob that enables it to lock/unlock the car when the fob is in close proximity to the car. Turn the switch to the off position and it should not lock/unlock unless you push the button. If it continues to lose sync with the car, try programming the fob through the DIC - there is a fob training option (see owner's manual) and that may work. If neither of those two things work, then it may be in the receiver in the car.

Moving this to C5 Tech.

 

Jack thank for the response. But I have done this all of what you are asking. And still no luck. It seams that the lock button on driver side door only unlocks but will it lock both doors. With the key in the driver side lock cylinder the key will pop the trunk but won’t lock driver door in conjunction with driver door. But if I got to the passenger side door it will lock and unlock both doors and pop the hatch. So I feel like somethings going on with the driver side door module wiring I have not checked the wires in the Accordion plastic piece that connects the door to the body of the car.

 

My vote is you DO have broken solder joints on the PCB in the fob. It is not easy to see them by eye. When you press the lock and unlock buttons on the fob to resync it to the car you are applying pressure to the PCB board and flexing it and momentarily "fixing" the broken solder joint(s). The fob works for a while and then the bad joint(s) open up again. I had the same symptom as you and reflowing the solder joints fixed it--I had a microscope at work and did find broken joints. That was 4 years ago and my fob has worked fine since then. The door modules have nothing to do with Key fob programing. I don't know what is causing the issue with you doors.

 

Just for Sh*ts and Grins and to satisfy my through process, PLEASE read and post all of your DTC. Use the internal DTC reading system.

IF, you have tons of old history DTCs i recommend that you clear the DTCs and see what comes back. Please report what you get. That will help troubleshooting.

READING YOUR C5 Engine Diagnostic Trouble Codes (DTC)



This procedure should be carried out any time you experience a problem with your C5. Most inexpensive store bought aftermarket code readers will ONLY read power train DTC’s. Reading the DTC’s with the C5 built in code reader will allow you to read ALL the modules in the vehicle.



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 the OPTIONS button

4) While holding OPTIONS, press FUEL button four times within a 10 -second period.



Initially, the on-board diagnostics go into an Automatic Mode which will cycle through each module and 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 module. ( 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 types of diagnostic codes, Current and History designated with a letter suffix, “C” or “H”. A current code indicates a malfunction is present 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 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 RESET 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. There are a few body module DTC’s that if set will prevent the module from operating properly. Once the DTC is cleared, the module will return to full function. This is not true for power train DTCs.



If you have never read and cleared your codes, there will probably be a lot of old history DTCs. It is recommended that you clear your codes and see if any come back during a driving cycle. Those are the ones that you need to concentrate on diagnosing.



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.



NOTE and a WARNING. You can read the DTCs while the engine is running. I pull mine up all the time while driving.

WARNING. Don’t become distracted while reading DTCs while your driving and cause an accident!!!!! Use common sense and drive safe.



These are some very good C5 Diagnostic Trouble Code (DTC) explanation web sites!!! They also explain how to read the DTCs



Here are some very good sites that explain what DTC mean:



http://www.gearchatter.com/viewtopic11755.php



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



Make sure to include the H or C suffix when you post your DTCs!!



NOTE!!! Start the car and let it idle. Then take it for a drive and cause the problem to occur. When you return home pull the codes BEFORE you shut off the engine.


Do NOT discount the codes with the H following them. They can provide an audit trail for issues going on with the car. They ARE important in diagnosing problems.

Post ALL the codes that you pull with the engine running..........

Some codes go away WITHOUT setting an H code when you shut the engine off. I suspect you will have several codes that will show C or HC that do NOT show when the engine is turned off.

 

28-tcs c1255 h
40-bcm b2723 h
58 sdm b1001 h
u1016 h
u1040 h
u1096 h
ao-ldcm b2282 h
b2284 h
u1255 h
u1064 h
u1016 h
u1096 h
ai- rdcm b2253 h
b 2283 h
b2285 h
u1255 h
u1064 h
u1016 h
u1096 h
bo rfa u1096 h
u1064 h
c2100 h
c2110 h c
c 2115 hc

 

LOL!! EXACTLY what I thought.

NOW,, Go back and clear out the DTCs in eash module until they are ALL GONE. Drive the car and see what shows up. Remember Read the DTCs BEFORE you turn the ignition OFF. Some DTCs clear after each ignition cycle. Its also a good practice to read then right after you start the engine.

Bill

 

Thank you. As soon as I get back from the body shop I will. I’m having some paint work done.

 

You could also upgrade to a 2001 to 2004 RFA system. Fobs , tpms are all cheaper and work better.
http://www.superchevy.com/how-to/vem...97-2000-model/

 

[QUOTE=Bill Curlee;1599887060]LOL!! EXACTLY what I thought.

NOW,, Go back and clear out the DTCs in eash module until they are ALL GONE. Drive the car and see what shows up. Remember Read the DTCs BEFORE you turn the ignition OFF. Some DTCs clear after each ignition cycle. Its also a good practice to read then right after you start the engine.

so I went on a Small road trip cleared the codes before the road trip I just got back and there is no codes present not sure what to think of it.
But i I am now noticing a little bit of a sputter when in higher rpm when getting on it. But. No codes. I thought it was just the exhaust noise changing but it’s unmistakable theres slight a sputter of some sort I just had spark plugs wires and one coil replaced it does have borla exhaust. Car run good at idle. And drives great. Just when I get into the gas alittle hear and feel the sputter.

 

[QUOTE=Joshsls1;1599899093]Ok done. I cleared and Then went for a Drive. No codes are present. Nothing came back. Checked while car was running and while off.

 

How did you check codes while the car is running? can you do it the same way with the dash buttons? I had my mechanic plug in his reader right after an active handling notice came on momentarily and service active handling notification comes on, After this happens a few times the active handling light on the dash comes on.
The lights are not on when you start the car again, but after 10 to fifteen miles it starts again every time.

I had the active handling problem so i removed the EBCM solder the appropriated spots and reinstalled it. Everything was fine for a few weeks and then the problem started again. I removed it again and this time sent it out to be repaired. The guy i sent it to called me asked a few questions and then said he would test it and let me know. He told me he found the 2 problems and repaired them. He sent it back to me and i installed it. After about 10 or 12 miles it started, the active handling on the dash came up and the brake would shutter a bit. After that happened a few times the active handling light comes on and stays on. The dash says service active handling soon. I had cleared all the codes so I checked to see if there were any new ones. The code 28TCS C1287 Came up I cleared the codes a couple times and drove the car again and get the same results every time. Does anyone know if the sensor on the steering column is bad could that be the problem with everything? And I did check the grounds up on the wheel wells and they seem to be good but i cleaned them anyway and the problem is still the same.. The people who did the work on the EBCM have offer to check it again but if the problem is all being cause by the steering column sensor i don't want to send the module out again. Has anyone had a similar problem? The car is 2004 (C5)
And anyone know a good vette mechanic in MA. I live near springfield so even connecticut would be fine, Thanks for your Help everybody. And any good place for parts?

 

Its easy. Just clear any messages in the DIC by pressing and holding RESET and do the same thing that you do when you are stopped. Just don't wreck while you do it!

 

Thanks

 

Did you ever resolve this? Mine is doing the same thing. I can get the fobs to program and they work fine. I start the car and shut it off, fobs don't work anymore. My EBCM is shot I think (Active handling/ABS lights on). The fobs stopped working long before the EBCM went bad.

I don't drive the car that much so I just use the key but it is still annoying.

 

Something to check:

1. Is your 12 VDC battery in Tip Top shape. When you crank the engine,,, if youn read the battery terminal voltage, how low does it drop when the starter first kick in??
2. Have you taken your FOB apart and inspectged the circuit board? Use a magnifing glass and look for cold/cracked solder joints.
Please report back

Bill

 

At one point I replaced the battery all together to try to fix this and it still forgets the programming. I'll look at the voltage drop when I get home tonight regardless.
I have 2 fobs and both do it so I'd think it isn't fob specific... both lost programming at the same time.

 

Excellent!