FOB not detected - again
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FOB not detected - again
I have a 2015 Z51 with automatic. The FOB (both of them) stopped operating normally. Won't start the car in the morning. When I leave work in the evening, they work fine. Took the car to the dealer for noise related issues and explained the problem to them They said they could not duplicate the issue. I'm a little skeptical since they had the car for an entire week and the car never recognizes the FOB in the morning. They claimed to have tested the FOB's batteries and the car battery. All checked out. The car is garage parked at night. I've seen some FOB related problems on the forum, but never one such as this where it works in the evening, but not in the mornings.
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
When it fails to recognize the FOB, try placing it in the slot on the steering column.
http://forums.corvetteforum.com/c7-g...s-and-rke.html
The link has a bit of help on FOB not detected situations.
Elmer
http://forums.corvetteforum.com/c7-g...s-and-rke.html
The link has a bit of help on FOB not detected situations.
Elmer
Last edited by eboggs_jkvl; Nov 5, 2017 at 09:51 AM.
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It is likely something was installed in or near your home that is interfering with the fob. The C7 fob operates on 433 Mhz. which is also used by many other devices including garage door openers, weather station remote receivers, alarm sensor systems, wireless thermostats, and various other RF remote control devices. It is in a frequency range that is license free around the world so regulation is quite limited and the potential for more issues is large-especially with a lot of devices coming in from the far east that don't bother complying with the limits set for output level and spectral purity.
If you installed anything new in your house recently that is remote operated or communicates remotely (garage door, sensors, etc.) then you can try temporarily turning that device off. However it is likely one of your neighbors has something that is creating the interference. In any case this is probably why it doesn't work at your home but works fine when leaving work.
315 Mhz. used to be the most common fob frequency in the U.S. but since that isn't available for use in many countries the move is on to 433 Mhz. and co-interference issues are likely to increase. Other devices won't be able to start or unlock your car but the radiation level from them "de-senses" the remote transponder in the C7 so it doesn't hear/respond to your fob. A new fob battery may help at least temporarily since that does increase the effective output power from your fob.
If you installed anything new in your house recently that is remote operated or communicates remotely (garage door, sensors, etc.) then you can try temporarily turning that device off. However it is likely one of your neighbors has something that is creating the interference. In any case this is probably why it doesn't work at your home but works fine when leaving work.
315 Mhz. used to be the most common fob frequency in the U.S. but since that isn't available for use in many countries the move is on to 433 Mhz. and co-interference issues are likely to increase. Other devices won't be able to start or unlock your car but the radiation level from them "de-senses" the remote transponder in the C7 so it doesn't hear/respond to your fob. A new fob battery may help at least temporarily since that does increase the effective output power from your fob.
Last edited by NSC5; Nov 5, 2017 at 11:28 AM.
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
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DO the "FOB not detected" steps. It might actually help. If the FOB batteries are good and the car battery is good, there are other things that could be causing the FOB to not be detected. You have to read the PDF yourself. I wrote that up to help people.
Elmer
Elmer
Last edited by eboggs_jkvl; Nov 5, 2017 at 11:28 AM.
Burning Brakes
Joined: Dec 2010
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From: SoCal
I just had this happen with mine on a rather cold morning, had to do the manual entry with the alarm and everything. But honestly, mine is a '14 and I hadn't changed the batteries in the fobs yet. Why not just change them out to be sure? It might cost $5 and then you'd know for sure it isn't your (rather old) batteries.
Melting Slicks
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From: Thomas Texas
It is likely something was installed in or near your home that is interfering with the fob. The C7 fob operates on 433 Mhz. which is also used by many other devices including garage door openers, weather station remote receivers, alarm sensor systems, wireless thermostats, and various other RF remote control devices. It is in a frequency range that is license free around the world so regulation is quite limited and the potential for more issues is large-especially with a lot of devices coming in from the far east that don't bother complying with the limits set for output level and spectral purity.
If you installed anything new in your house recently that is remote operated or communicates remotely (garage door, sensors, etc.) then you can try temporarily turning that device off. However it is likely one of your neighbors has something that is creating the interference. In any case this is probably why it doesn't work at your home but works fine when leaving work.
315 Mhz. used to be the most common fob frequency in the U.S. but since that isn't available for use in many countries the move is on to 433 Mhz. and co-interference issues are likely to increase. Other devices won't be able to start or unlock your car but the radiation level from them "de-senses" the remote transponder in the C7 so it doesn't hear/respond to your fob. A new fob battery may help at least temporarily since that does increase the effective output power from your fob.
If you installed anything new in your house recently that is remote operated or communicates remotely (garage door, sensors, etc.) then you can try temporarily turning that device off. However it is likely one of your neighbors has something that is creating the interference. In any case this is probably why it doesn't work at your home but works fine when leaving work.
315 Mhz. used to be the most common fob frequency in the U.S. but since that isn't available for use in many countries the move is on to 433 Mhz. and co-interference issues are likely to increase. Other devices won't be able to start or unlock your car but the radiation level from them "de-senses" the remote transponder in the C7 so it doesn't hear/respond to your fob. A new fob battery may help at least temporarily since that does increase the effective output power from your fob.
A friend of mine installed an after market laser light in the door. It shined down on the ground the Corvette logo when he opened the door. When he closed the door, it would take a minute or so to shut off. During that time, the car would not start. Discovered this laser device was emitting enough RF noise, that kept the car from communicating with the FOB. He wrapped the device in aluminum foil and it fixed the problem.
I would start shutting down electrical devices near the car one-by-one until you find the offending device. Look at anything with a transformer or electric motor including florescent lights.
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Thread Starter
Advanced
Joined: May 2016
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It is likely something was installed in or near your home that is interfering with the fob. The C7 fob operates on 433 Mhz. which is also used by many other devices including garage door openers, weather station remote receivers, alarm sensor systems, wireless thermostats, and various other RF remote control devices. It is in a frequency range that is license free around the world so regulation is quite limited and the potential for more issues is large-especially with a lot of devices coming in from the far east that don't bother complying with the limits set for output level and spectral purity.
If you installed anything new in your house recently that is remote operated or communicates remotely (garage door, sensors, etc.) then you can try temporarily turning that device off. However it is likely one of your neighbors has something that is creating the interference. In any case this is probably why it doesn't work at your home but works fine when leaving work.
315 Mhz. used to be the most common fob frequency in the U.S. but since that isn't available for use in many countries the move is on to 433 Mhz. and co-interference issues are likely to increase. Other devices won't be able to start or unlock your car but the radiation level from them "de-senses" the remote transponder in the C7 so it doesn't hear/respond to your fob. A new fob battery may help at least temporarily since that does increase the effective output power from your fob.
If you installed anything new in your house recently that is remote operated or communicates remotely (garage door, sensors, etc.) then you can try temporarily turning that device off. However it is likely one of your neighbors has something that is creating the interference. In any case this is probably why it doesn't work at your home but works fine when leaving work.
315 Mhz. used to be the most common fob frequency in the U.S. but since that isn't available for use in many countries the move is on to 433 Mhz. and co-interference issues are likely to increase. Other devices won't be able to start or unlock your car but the radiation level from them "de-senses" the remote transponder in the C7 so it doesn't hear/respond to your fob. A new fob battery may help at least temporarily since that does increase the effective output power from your fob.
I had considered that. The reason I don't believe it's an electrical interference is the car will start up after I've pulled into the garage and let it sit for a few hours. Only the first morning start up has the issue. I'm going to put in a new battery and see what happens. Thanks!
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From: Sacramento
I just had this happen with mine on a rather cold morning, had to do the manual entry with the alarm and everything. But honestly, mine is a '14 and I hadn't changed the batteries in the fobs yet. Why not just change them out to be sure? It might cost $5 and then you'd know for sure it isn't your (rather old) batteries.
Just use a cheap *** volt meter (sometimes free at Harbor Freight) and make sure it has 3 volts.
