Key fob batteries

[bluenose1940]

Hello folks,

Tried to open my car this morning but can't get anything from either of my keys.  I have tested the batteries in both and the readings are 2.99v in the one I have been using daily, and it shows 2.95v in the spare.

Is this not enough power to open the doors?

[royoftherovers]

1 minute ago, bluenose1940 said:

Hello folks,

Tried to open my car this morning but can't get anything from either of my keys.  I have tested the batteries in both and the readings are 2.99v in the one I have been using daily, and it shows 2.95v in the spare.

Is this not enough power to open the doors?

This is not a joke Geoff, but hold the keyfob next to your head (above the ear) and see if that works.

[steve2006]

Apart from the fob problem is the car functioning normally itself once your in it?

[bluenose1940]

Hi chaps, thanks for coming in on this problem.  Very strange, I can't even open the doors with the mechanical key.  just going to have a look in the manual to see if I can open the tailgate with the mechanical key.

 

[steve2006]

Sounds like the 12V Battery if completely unresponsive.

[bluenose1940]

Yes I was thinking that.  How do you get over a problem such as this if the mechanical key won't work?  

I was out in the car on Tuesday and so the 12v Battery shouldn't be flat.  I wonder if I left something on!!!!!!!

[steve2006]

AA/RAC/Lexus Assist ?

The locking system needs vehicle power to operate the door lock motors but there has to be a way to access the car if the Battery is flat.

[bluenose1940]

Yes I have Lexus Recovery but they'll have the same problem, just can't get in electronically or mechanically.

[steve2006]

Not sure if this is correct but apparently you need to turn the mechanical lock with the key and pull the door handle at the same time.

[steve2006]

If you have Lexus Recovery the problem then becomes theirs not yours, there has to be a way even if it means them getting underneath to access the bonnet release to get to the electrics.

[NemesisUK]

Not so straight forward using the mechanical key!

From the handbook -

• Unlocking the door
• Insert the mechanical key while pulling on the driver’s door handle.
• Unlocking the door. (turn the key clockwise)
• Remove the key, return the handle, and then pull the handle again.

[bluenose1940]

1 minute ago, steve2006 said:

If you have Lexus Recovery the problem then becomes theirs not yours, there has to be a way even if it means them getting underneath to access the bonnet release to get to the electrics.

I have followed the procedure.  You have to pull the handle to get at the keyhole, you then insert the key and turn it, take the key out and let the handle go back to its normal position and the pull it again to open the door.  Didn't work though.

[bluenose1940]

Any recommendation for a new 12v Battery and anyone know of any good deals at the moment?

Is the dealership a good place to go?

It's likely to be my Battery I think as the car is 7 years old and I'm pretty sure that it is the original.

[steve2006]

Have you managed to open the boot with the key?

I would try Lexus first for a Battery, the AA replaced my stop/start Vauxhall Vivaro one at around the £200.00 mark due to the type.

[Herbie]

Before you spend money on a 12V Battery, lubricate the key and lock. They often go very stiff due to not being used and may even need a pair of pliers to 'assist' the turning force.

The batteries in the key fobs are shot at, or at least that would be my guess. 2.9V no load is a low reading - put load on them and they'll drop even further.

EDIT: had a bad night, didn't drop asleep until 7am so just got up. Re-read your post and I don't think it'll be what I said but I can't delete, only edit

[bluenose1940]

Well chaps, the AA chap has just left and he managed to sort it.

He tried all sorts and nothing worked, he couldn't even get the mechanical key to work.  After  a while he went and sat in his van and was fiddling about with the fob and, I was stood by my car when it suddenly unlocked!  When I asked him how he managed to do that he said that he had 'cleared the capacitors' because the fob had apparently become out of sync.  I didn't realise that such a thing could happen.  Because I was so chuffed that he had been able to sort it, I foolishly forgot to ask him why the mechanical key didn't work.  I must go out and try that in a minute.

I now know what to do if this happens again.  You simply take the Battery out and hold the buttons in for 20 or 30 seconds, and this clears the capacitors.

I do still have one other problem though, and that is, my spare fob doesn't actually work despite my fitting a new Battery in it.  Does anyone know if these are repairable?

Thanks again for all the input.

 

 

[Herbie]

3 minutes ago, bluenose1940 said:

When I asked him how he managed to do that he said that he had 'cleared the capacitors' because the fob had apparently become out of sync. 

People always laugh or moan when I say, "Have you turned it off and back on again?" but it's a well-known phrase because it really does work a lot of the time.

Any electronics can 'get their knickers in a twist' at times and a good old power cycle to allow said knickers to untwist can be just what the doctor ordered.