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Hey all. I recently bought a 2008 C6, and started having problems with the car giving me "No key fob detected" errors (either when i shut the car off, or when i go to start it). I replaced the batteries AND programmed a new (3rd) key FOB using the instructions found on the forums. Still having issues.
The car will lock/unlock/open the trunk with the key fob WHILE im having issues with the "no key FOB detected" errors.
Could it be a problem with the system antenna or something? It's got to be on the car side at this point.
The car will NOT start using the slot in the glove box during these issues (despite being able to program a new fob using that slot). Eventually the car will start, with no rhyme or reason why it suddenly detects the FOB.
Also seems like when the car sits, its less likely to do it (example: i drove the car this morning and it started up no problem, but when I went to shut it off after a 30 min drive I get the missing FOB error).
ANY help is appreciated! Worried the car is gonna strand me somewhere now.
Is this something you are going to try to fix yourself or do you want to know what your issue “may be” before bringing the car to a shop?…do you at least have a 12 volt test light and a DVOM ??…do you have a scan tool (not a code reader) to check for trouble codes ??…is the FOB installed correctly into the slot ??…when FOB not installed into the slot and car attempting to start do you hear ONE click or a series of clicks when car is trying to start ??…one click is usually a bad RCDLR.
Is this something you are going to try to fix yourself or do you want to know what your issue “may be” before bringing the car to a shop?…do you at least have a 12 volt test light and a DVOM ??…do you have a scan tool (not a code reader) to check for trouble codes ??…is the FOB installed correctly into the slot ??…when FOB not installed into the slot and car attempting to start do you hear ONE click or a series of clicks when car is trying to start ??…one click is usually a bad RCDLR.
Thanks for the reply. I'm going to try and fix it myself first.
-The FOB is installed correctly into the slot, with buttons toward the passenger side. This is the same orientation I programmed the new FOB to the car. So it should work.
-There are a series of clicks when attempting to start the car when getting the "FOB missing" error on the dash.
-I have a test light and a DVOM
-I have a code reader, but not a scan tool
I'm also searching around to see if i can find any threads/video with a similar set of symptoms. Thanks again!
The Remote Keyless Entry (RKE) system is susceptible to electromagnetic interference (EMI). There’s a section in the owner’s manual that speaks to it. Cell phones, Bluetooth devices, cell phone chargers, usb chargers, fluorescent lights etc have all been linked to fob communication issues. I’ve had the fob not found message from having the fob in the same pocket as my phone, from having the fob in the same pocket as the fob from our DD, and from the lighting in a gas bar. I’m sure you can come up with your own plan to eliminate this issue as a possible cause.
There is a TSB concerning this issue..do diagnose these cars you really need to have a “factory level” or similar aftermarket scan tool…code readers are only used to see and clear Powerplant codes…that’s it !!..if you need some more help I can use my 2008 to help you diagnose this…it’s a slow day today…with a scan tool I’d check to see if I can communicate with the RCDLR…if not checking that module for proper power and grounds would be my first check…car should start using back up antenna.
Thanks a lot for the replies. I'm at work so trying to read in between breaks! Im definitely going to try and eliminate interference as a potential problem first. It has both happened and NOT happened in the same location though, multiple times. But i will eliminate as many variables as possible. Unfortunately I do not have access to a scanner tool.... Would we expect a problem with the RCDLR to affect ONLY the start function of the vehicle though? Again, it locks and unlocks just fine even when having the issue. I will do some more testing after work, thanks again for all of the help.
You would expect a bad RCDLR to affect both the door lock/unlock functions too…2 separate systems…the funny thing is your car will not start with the FOB using the backup antenna in the glovebox…access the antenna connector and you should NOT see the test light illuminate when test light connected to ground with ignition on probing the orange wire…when connected across Pins A and B with AC selected on your DVOM you should see some AC voltage…it will move around so if your DVOM has a “min-max” feature it will be easier to check…I saw .780 volts max….I checked resistance across the backup antenna and saw .9 ohms…no published info on this though…a few years ago I was having FOB issues on my Toyota 4 Runner…turns out my cell phone power pack which I used to keep plugged in prevented the doors from locking and unlocking and probably had a bad diode in it which was back feeding voltage into the car…that was a fun one to diagnose.
You would expect a bad RCDLR to affect both the door lock/unlock functions too…2 separate systems…the funny thing is your car will not start with the FOB using the backup antenna in the glovebox…access the antenna connector and you should NOT see the test light illuminate when test light connected to ground with ignition on probing the orange wire…when connected across Pins A and B with AC selected on your DVOM you should see some AC voltage…it will move around so if your DVOM has a “min-max” feature it will be easier to check…I saw .780 volts max….I checked resistance across the backup antenna and saw .9 ohms…no published info on this though…a few years ago I was having FOB issues on my Toyota 4 Runner…turns out my cell phone power pack which I used to keep plugged in prevented the doors from locking and unlocking and probably had a bad diode in it which was back feeding voltage into the car…that was a fun one to diagnose.
Thanks so much for the info, man.
So I uhh, feel pretty silly, but i think i figured out what it is. I installed a uniden radar detector and dash cam in the car, and they are connected to the cig lighter port. Since that port is always hot, I unplug them when I park the car. This is why it seems to start "after it sits a while", because I have that unplugged. Then when I arrive at my destination, they are still plugged in when I go to shut the car off and so I get those "missing FOB" errors.
I just tested this in my driveway, it reliably turns the issue on/off when I power on my radar detector.
So a simple interference problem that seemed intermittent, but it was me.
Key FOB "missing"- Intermittent issues
