Key not opening car from outside but locking ok

[BazaM78]

09 avensis, key will lock ok, but now the open button won’t work, key lights up and after a number of presses 20+ will open the car. The boot button never has worked. 

I can get in with the key, with alarm going off, a few presses of the open button will disable. 

I tried the open door, wait 10 sec with key in on position and press button twice, nothing.

key will open and close while sitting in the car with doors closed every time. 

changed Battery same outcomes

please help

[Crustyoldavensis]

My 2004 Avensis used to do this. 

I removed the lock button from my key. No more issues.

[Konrad C]

If this happens everywhere, then transmitters can be eliminated. Try a auto locksmith which specialise in remote keys. They can check the key and the car to see why the open signal is not getting through. Years ago when I owned my Mk1 '98 Avensis, I did have a similar problem with a key going out of sync. The owners manual covered this out of sync issues and how to resolve it. I think it changed when the next model was introduced, so used another procedure.

Do you have two remote keys? I have all the keys that came with my 2009 car - 2 remotes and grey valet key. I alternate between the remote keys, so prolongs the good condition keys.
Do you have any wireless devices that could be causing interference, like wireless rear Dashcam? 

[BazaM78]

No additional keys, no wifi devices other than phones, got the sequence to add reset and wipe, cleared and added my key, has a slight improvement (not as many presses) might be receiver? Is there one in the ds door? 

[Gerg]

I would be tempted to buy another brand new key Battery and see what happens after you've fitted that, just to be doubly sure!

I had a broadly similar problem with an intermittently-used Mazda remote - if you kept trying over and over it would eventually open the door.  I was fairly certain it was a bad solder joint to the key fob button.  It wasn't, it was the Battery giving those symptoms.  How come?  The closest I could get to an explanation was that as the Battery is being used to operate the key fob, over and over, it warms itself up slightly (or maybe the heat of your hand?), this could cause the available voltage to increase a little, and then finally the voltage is enough to operate the key fob properly.

Only a theory! 

I finally noticed that both Mazda key fobs were doing it (the car was not being regularly used). Two new fob batteries fixed that problem.

If the resting voltage of the battery, new or old, is near 3.05 volts (measured on a digital voltmeter, obviously) then the key fob will be into a 'will it/won't it' area - I've discovered this from checking lots of ailing keyfob batteries, and also some other devices that use CR 2032 button cells. From my experience, a new cell should be over 3.30+ volts.

Perhaps you knew all that anyway...

 

[BazaM78]

I have changed the Battery, being the cheaper option I’ll try again. New Battery could have been near EOL.
 

had read about voltage levels in other posts but always good to get reminders.

[BazaM78]

Got a new Battery today, works from front door now. The replacement Battery I originally had must have been near its end even while new

[2009joe]

On 1/11/2022 at 3:58 PM, BazaM78 said:

09 avensis, key will lock ok, but now the open button won’t work, key lights up and after a number of presses 20+ will open the car. The boot button never has worked. 

I can get in with the key, with alarm going off, a few presses of the open button will disable. 

I tried the open door, wait 10 sec with key in on position and press button twice, nothing.

key will open and close while sitting in the car with doors closed every time. 

changed battery same outcomes

please help

if causes much bother through the times you can buy a  eBay keyless entry system that can be wired into the cars drivers door locking system and be a good enough job as i did that to a car i had with electronic locks but not key remote system