Having trouble with no fob detected. Fob battery is brand new. Is the ignition proximity sensor in the ignition switch itself? I have a new switch I can put in there but don't wan to fuss with it if that's not the case.

Thanks!

 

all the time? intermittently? mine does that if its in the wrong pocket...wifes does it if its in her purse too far away in passenger seat

 

It’s not in the ignition switch. There are 2 antennas, 1 in each B pillar, and one behind the slot to the left of the glove box. The antennas do a triangulation to make sure the fob is in the cabin when you try to start the car. I’ve attached a fob not detected check list.

 

Check the voltage of the battery in the fob. Be sure to buy fob batteries from someplace that sells lots of them, like Walmart.

Fob in your pocket with something else?

 

A couple of times I hit the unlock button inside the car and it started right up-just put a new duracell in it and works great.

 

Intermittent. As long as it's extremely close to the ignition, I'm good. Or.in the glove box. Anywhere else, it struggles.

 

Fob usually sits on the cup holder.

 

Sure sounds like a weak fob battery. I know they make lithium ion 2032 batteries such as Energizer and Duracell. They should last a long time too. Other than that, the antenna behind the glovebox slot has been known to become detached and slip down, but the easiest first step is to put in a new fob battery. Just make sure it is put in the right way up.

 

the main receiver is mounted in the center of the dash above the HVAC box.

 

The only receiver, the RCDLR, is mounted above the head unit, but it’s the antennas connected to it which pick up and send signals to and from the fob.

 

Check the proximity of your Smart phone. On my 08 with a Proclip mount near the center of the dash, I'll get a no fob detected every time unless I move the phone to my left side near the driver's door.

 

Check the voltage of the fob battery, should be 3.3 VDC, just because you recently bought one doesn’t mean it hasn’t been sitting on a shelf for a while.

 

4 antenna's, with one at the glove box slot, one on each side of the B pillars (gas cap locations), and one at the back of the car.

Only one antenna has to pick up the fob to allow you to get into the car, but 2 have to pick up the fob, to prove that its in the car itself to allow the motor to start.

So short of doing a tech 2 test to make sure that all the antenna's are working, you could place the fob in the back hatch between the rear and passinger side antenna, if you suspect that the glove box or drivers side anenttas are having problems. Hell trick works well, when someone swaps out the dash lights to LEDs, the leds are putting out too much RF noise, and gets the fob away from the front of the cabin/away from the RF noise to allow two antennas to pick up the fob to start the car.


As for new battery, remove the cables from the battery terminal, touch the cables ends to themselves away from the battery to de-power all the modules a few times (with be a light spark the first time), then reconnect the battery. The modules will drain down on their own if not powdered up by the battery and enough time elapses (30 min or more), but it not enough time during battery replacement, then cables touched together will drain the modules of all current instantly and allow al the modules to hard reset when the battery is reconnected. Hence module can lower power gltich when you try to start the car with dying/drained battery (the get less than 12 volts to low voltage glitch them, and until they are drained all the way down of no current still retained in the capacitors, to re-hard set them, will stay glitch with battery change to quickly instead.

 

Happened after acquiring a flip phone.
Got NFD w/ fob & phone in same pocket.
Seperating all was well.
Thank God I recalled reading right here this NFD may occur w/ phones.

 

One thing to inspect for is the claw-looking metal battery spring that is soldered to the circuit board. Make sure the solder connections have not failed.

If you see any previous battery crusties, that will create a drop in voltage, creating the problems you have. Each contact should be cleaned up. Also, the gold pad on the circuit board that the contacts on the lid touch, likely will benefit from a cleaning with a fresh eraser. Don't use an eraser that has become old and smeary.

 

Wanted to bump this to the top now that I have an answer. I had irregular unlocked and door opening. Many times I had to manually push the unlock button. I thought maybe the metallic tint, or the old door handles, etc. etc. etc.

Finally, I quit being cheap and bought a new remote. ALL PROBLEMS HAVE RESOLVED. I bought an OEM remote, programmed it, and I haven't had a single issue since. Well worth the $110 from the frustration alone.

So, if you've tried all the cheap options, just go ahead and replace the remote. It's probably the the issue. Good luck all!

 

I was going to say the same thing ..I had all the fob not detected issues.. tried a eBay fob and it worked for a few weeks. Broke down and bought a GM fob and haven't had a fob not detected in 2 years

 

This may sound strange, but i find myself having to "press together" the fob casing every so often to get the internals to make full contact. Fixes it every time, until I have to do it again. I figured this out after putting in a brand new battery, it would seem I may have potentially damaged something, or the internals are wearing out.

 

Trying to understand the exact problem and what you did to solve it. Seems that you had random proximity detection issues but you could always hit the unlock button and get in the car? After you get in the car, did the system detected the fob and you were able to start the car, even if you had to move the fob around inside the car but never had to use the glovebox slot? It looks like the problem has been resolved for the past 3 days with a new OEM fob, but since it was a random issue, do you think it has had enough time to guarantee the issue is resolved with just a new GM fob? My 08 is having random issues when trying to unlock a door or hatch. I have two OEM fobs with new batteries and sometimes the car will recognize the fob both through the proximity system and through the push of the fob's unlock button and sometimes neither fob will work to open the car doors or hatch. I was thinking the RCDLR had an issue but buying a new GM fob sounds like a much easier solution.