Door not unlocking

[Rimmy]

Hi

 

problem with my 2016 A4. Nothing happens when I try to unlock car with fob. (Same with second key). I then open manually with key, alarm goes off (annoying). Then I need to place back of key fob in centre console to get the ignition on and car then starts. After that the key works for a while (ruling out any issue with key). But then the problem reappears. 
 

anyone any idea what’s wrong? Appreciate any help. 

[JMKC82]

Hi Mark,

Assuming you've changed the battery on the key.  Happened to me.  When i grabbed the second key, it also didn't work, but the second key was sat in the cupboard for about 3 years.  Changed the battery, and all good.  When you change the battery (use a good brand), you might need to put the key back on the centre consol.

Secondly, always good to know the alarm is working properly 😉 .  Better to know it works, than when you need it and it doesn't work 😛

Joe

[Rimmy]

  On 9/8/2022 at 8:18 AM, JMKC82 said:

Hi Mark,

Assuming you've changed the battery on the key.  Happened to me.  When i grabbed the second key, it also didn't work, but the second key was sat in the cupboard for about 3 years.  Changed the battery, and all good.  When you change the battery (use a good brand), you might need to put the key back on the centre consol.

Secondly, always good to know the alarm is working properly 😉 .  Better to know it works, than when you need it and it doesn't work 😛

Joe

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Hi Joe. 
 

once I go through the process of getting the car to start, do my journey then the key works perfectly to lock/unlock as normal. But when I go out in a few hours time it will be back to square 1. 

[JMKC82]

Hi Mark,

It could be just one of those things you are experiencing, with a low key battery?

But just to rule out 1 thing cheaply by changing the key battery, for less than £5??

[Rimmy]

  On 9/8/2022 at 8:30 AM, JMKC82 said:

Hi Mark,

It could be just one of those things you are experiencing, with a low key battery?

But just to rule out 1 thing cheaply by changing the key battery, for less than £5??

Expand  

Changed the battery this morning but still the same issue. 

[jdragon]

  On 9/8/2022 at 11:29 AM, Rimmy said:

Changed the battery this morning but still the same issue. 

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What brand of battery did you use? Guy at work had this exact issue, put the duracel in his fob from mine, and problem solved.

[Rimmy]

  On 9/8/2022 at 3:24 PM, jdragon said:

What brand of battery did you use? Guy at work had this exact issue, put the duracel in his fob from mine, and problem solved.

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Duracell too. But the fact it’s affecting both keys and both will either work or not work at exactly the same times suggests it’s not an issue with the key. 

[jdragon]

Were they brand new/in date batteries? It's important to rule this out.

My old A4 B8 started having an issue with unlocking/locking, and after some investigation I found the car battery voltage was around 12V so changed that anyway, and the initial problem with the fob went away too. 

[Rimmy]

  On 9/8/2022 at 5:37 PM, jdragon said:

Were they brand new/in date batteries? It's important to rule this out.

My old A4 B8 started having an issue with unlocking/locking, and after some investigation I found the car battery voltage was around 12V so changed that anyway, and the initial problem with the fob went away too. 

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Brand new. But it couldn’t be the battery if both battery’s are behaving in exactly same way, be that working or not working at exactly the same time. 

[jdragon]

  On 9/8/2022 at 5:46 PM, Rimmy said:

Brand new. But it couldn’t be the battery if both battery’s are behaving in exactly same way, be that working or not working at exactly the same time. 

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Best it to a garage.

[Steve Q]

Definitely recommend a diagnostic check. Could be a door module.