# Passive lock/unlock



## Robby (Mar 1, 2013)

Have you moved to a new home? Or are you still at the same address as when you purchassed the car?
Does the problem only occur at your home?

Sounds silly but proximity to a cell tower can do this.....or you live near a cell tower that has been recently modified for higher signal strength.

There is an area about five miles from my home....near a friends house, that nobodys remotes work correctly......a cell tower is within 1/8th mile and has been upgraded.....thats when the troubles began.

Get another quarter mile away and the problems disappear.

Just wondering if.....
Rob


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## NickD (Dec 10, 2011)

Installed a Duracell Pro 2032 in my remotes, last a long time, more expensive, but long term worth it. Not sure which battery your remotes use, LTZ was out of my class. Batteries that came with it were unbranded made in India, not knocking India, but sure knocking unbranded. 

Sure are not water proof, moisture, humidity, sweating hands can get in and cause additional leakage currents. Replacement cost is nothing short of being extremely outrageous.

Good 2032 should show 3.3 volts open circuited. Even at 3.2 V, will drop down very quickly, at room temperature.


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## ChevyGuy (Dec 13, 2014)

OK, looked up some info. When you push a button on the outside of the car, it sends a "low frequency" signal. When the fob hears that, it transmits back a RF "I'm here" signal. If it's the right fob, the car does what you expect. Looking at the schematics, I'm pretty sure the "low frequency" signal is in fact a magnetic field. The rated range is 1 meter. (about 3 feet). There are 6 transmitting antennas, one each driver and passenger door handle, two in the console, one just behind the rear seat and one in the trunk fascia. I think it's safe to say that if you're having problems both inside and outside, it's not the antenna wiring. 

What could be happening is your fob is close to something creating a magnetic field that causes it to run down it's battery. Perhaps one of those wireless charging stations for phones or tablets. I also wouldn't rule out a powerful magnet on the key chain interering with the range of the signal. Since it appears the car always responds to buttons on the fob, I wouldn't worry about the fob's transmitter or the car's receiver.

The keyless entry module is responsible for transmitting the low frequency signal. IIRC, it's on the outside of the right footwell.


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## hydrasport (Jul 15, 2012)

Thanks for the responses. The battery can be less than a day old and the issue still occurs. I have 2 fobs. One is seldom used and hangs where it has been stored for over 2 years. I have removed the possibility of interference from phones and other items. I can hold the fob in my hand next to the car and the car should recognize the fob. No need to press a button on the door as that has never been necessary to unlock them. Just pull the handle and the door should be unlocked by the time I get that close. It has always worked that way until now. 
Yes, we are having issues both inside and out. After driving the car home, or to any other location, I have personally dealt with the issue of trying to turn the vehicle off only to see the "no fob detected" message in the dash. Trying to start the vehicle after getting in with no problem and getting the "no fob detected" message is a real concern. That is the main reason it was taken to the dealer. 
I think the dealer was just pressing the lock and unlock button and that is why they could not duplicate the issue. The buttons work at a very long range. I will have to show them in person what the problem is. No matter how many service writers are involved and no matter how many times the issue is explained, the true problem never seems to get relayed to the tech.


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## hydrasport (Jul 15, 2012)

To add another look at the problem I need to explain what happened today. I walked out to the car with my seldom used fob (#2), and tried to open the drivers door. Pulled on the handle until I felt like ripping it off the car. Nothing happened. We stood there talking about selling the car and about a minute later all 4 doors unlocked. The fob was in my hand. The car was not being touched. It took over 60 seconds for the doors to automatically unlock. Batteries are replaced in both fobs at the same time to prevent any dead battery issues. Yes, I have a plastic baggy of good replaced batteries (3.3 - 3.1 volts on all).


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## ChevyGuy (Dec 13, 2014)

Sounds like the car's not triggering the fob. If it's happening to both fobs, then it's the car. 

I have no idea why it would be so intermittent - especially both inside and outside. That strikes me as a unusual failure mode. At this point I'm thinking it's the wireless module (not to be confused with the receiver.) 

Question: Do you have anything plugged into the ODB2 port? if so, remove it. It might be "jamming" the car's bus and preventing it from working.


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## hydrasport (Jul 15, 2012)

Nothing plugged into the OBD2. It's getting more consistent now. I'll suggest the keyless entry module if I bring it back to the dealer again. I will also show them in person what the problem is, not relying on a service writer to take notes and pass them on.


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## boraz (Aug 29, 2013)

NickD said:


> Installed a Duracell Pro 2032 in my remotes, last a long time, more expensive, but long term worth it. Not sure which battery your remotes use, LTZ was out of my class. Batteries that came with it were unbranded made in India, not knocking India, but sure knocking unbranded.
> 
> Sure are not water proof, moisture, humidity, sweating hands can get in and cause additional leakage currents. Replacement cost is nothing short of being extremely outrageous.
> 
> Good 2032 should show 3.3 volts open circuited. Even at 3.2 V, will drop down very quickly, at room temperature.


i only buy chinese 2032's off ebay for ~15 cents each, use them in hardhat lights, flashlights, tire pressure gauges, thermomters, digital calipers etc...every new electronic gizmo i buy i get the one that takes 2032

no issues with the cheap chinese batteries


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## Daisy81 (Jun 17, 2012)

I hope you guys get it worked out. Let us know what the dealer says.


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## hydrasport (Jul 15, 2012)

I've got the cheap batteries ordered online and sony and duracell. All seem to have the same voltage and life. 
Don't really want to take the Cruze back to this local dealer. Long story with them and a long list of bad dealings. Little things like they wrecked our first Cruze when it was 5 days old and had to replace it with a new one. 3 trips, total of 9 days in the shop with corvette, under warranty, to get the shifter replaced. I think everyone here knows about the sticky steering issue with some of these cars and that was many trips to this dealer for that problem, which they could never duplicate. We just don't drive it on the highway much anymore. This rant is just to show that we are about fed up with GM service.


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## Daisy81 (Jun 17, 2012)

They haven't taken care of your steering?! There is a user here called Chevy Customer Care. It is a Chevy Customer Service representative. Tell them what is going on and hopefully they can make arrangements to get your car fixed. It's a known issue that has a different solution based on the year of your Cruze. Also let them know what dealer is refusing to fix a known issue of the vehicle so that Chevy can deal with that dealer. Good luck.


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## ChevyGuy (Dec 13, 2014)

hydrasport said:


> Don't really want to take the Cruze back to this local dealer.


What about another dealer? The Warranty is held by GM, not the dealer.


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## Two7elevens (Apr 26, 2014)

Actually, similar thing happened to my 2012 Ltz. Sometimes it unlocks and works. But sometimes, it starts and would say no key detected. Samething with shutting the car off.

It doesn't reduce engine power or anything so I'm not too concerned. But interested if it's fixable.


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## hydrasport (Jul 15, 2012)

It's back in the shop today. Would not detect fob. Wife was pissed and videoed the event. Left it at the dealer and this time they got to see what it was doing. 
Taking odds that the dealer will change batteries in the fob and say it's all they can do. Last time I brought the bag of good batteries that have been changed out of the fobs in the last 6 months.


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## dasjamie85 (Jul 29, 2013)

hydrasport said:


> I can hold the fob in my hand next to the car and the car should recognize the fob. No need to press a button on the door as that has never been necessary to unlock them. Just pull the handle and the door should be unlocked by the time I get that close. It has always worked that way until now.


I'm curious about this. I have a 2013 Cruze LT with the keyless start/stop and passive entry, but I always need to press the button on the door/s to unlock. It never unlocks by just being in range or pulling on the handle. Is this something that may have changed with the model years? I've check my settings and everything is set to work.


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## ChevyGuy (Dec 13, 2014)

dasjamie85 said:


> I'm curious about this. I have a 2013 Cruze LT with the keyless start/stop and passive entry, but I always need to press the button on the door/s to unlock. It never unlocks by just being in range or pulling on the handle. Is this something that may have changed with the model years? I've check my settings and everything is set to work.


I think the setting was covered in another thread. If you don't read the option carefully, it looks like you're just deactivating a chirp on unlock. You may have turned it off because you don't want your car making noise. But in fact you're deactivating the passive mode.


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