one key not working now

[notaGolfR]

Golf R 7.5 with keyless entry.

My wife's key remote will not open doors now. I swapped battery with mine & that didn't fix.

Apart from a failed remote, is there a setting I changed that may be the cause please?

[Sharkie]

It probably is the battery in the key.

I just had to replace both my R's keys and the car is 18months old! 1 went dead about a week before the other.

swapping them around made no difference

replacement batteries are 2 for about $9 at your local Coles and its a 5 min job.

[DV52]

Golf R 7.5 with keyless entry.

My wife's key remote will not open doors now. I swapped battery with mine & that didn't fix.

Apart from a failed remote, is there a setting I changed that may be the cause please?

notaGolfR:Hi and let me first apologize for going "techno" on you in my reply!

Do you happen to own a diagnostic cable, or do you know someone close who has one? If so, then perhaps the screens below can be useful:



The procedure to check the health of the key goes like this:

• have the suspect key inside the car and turn-on the ignition
• fire-up VCDS software and navigate to Adv. Meas. Values Option on the hex17 module (Instruments)
• Tick the entries in the screenshot - particularly:
  
  • Immobilizer Challenge
  • Transponder ID Key 1-Key Transponder ID
  • Transponder ID Key 2-Key Transponder ID
  
  

If the key is operating correctly, the entry in "Immobilizer Challenge" will be the same as one of the "Transponder ID Key" entries (I've shown a not registered key in the picture above)

Don

[gregozedobe]

I'll leave the hi-tech stuff to Don (he does it extremely well )

I'll give you some lo-tech suggestions to try (I apologise if it seems too simplistic, but even if you are experienced it can often be worthwhile stepping through a logical fault-finding diagnostic process:

1: Does the red LED in the remote flash when you press a button (any button) ?
If it doesn't, then you have a problem with the remote. Most common cause is a battery low in charge
Get a new, known good battery (and confirm it is good by testing it out in your working remote).
Check there is no corrosion on the battery contacts. If there is clean it off.
Make sure it is installed the right way up (+ symbol up)
Still no red LED flash - definitely a problem with the remote.
Unfortunately they are expensive and the car needs coding to recognise a new one (bring along all keys)

2 If you have a red LED flash but the car doesn't respond (assuming you are not 100s of meters from the car)
Either the remote isn't actually sending a signal, or the car isn't recognising it as legitimate.
If the latter then the car may have to be re-coded to recognise the remote signal
(but IIRC this is pretty rare unless someone has been fiddling with coding eg VCDS, OBDII long coding, ODIS etc)

[notaGolfR]

Cripes grego. No need to worry about over-simplicity with me. I often ask for help in a style as if to a 7-year old. I do my "help" replies similarly.


I will try your suggestions and thanks a lot. I'd never noticed that red LED until I looked for it today, maybe because I'm a leftie & it gets covered by the way I hold the device. Excellent advice re battery handling. I used to sell them & always advised people to clean all contact surfaces (device & battery) regardless of evidence of corrosion and hold the battery in a tissue to avoid contamination from skin. I always wear a condom too


Another reply mentioned doing a sync of the keys. Believe it or not I DO consult the damn manual but it's a bastard book and might have missed the sync bit.

[notaGolfR]

I am concluding the remote is faulty. A good battery failed to make the red LED flash.

Have also tried syncing. As is typical, following the book, that requires flipping from p.70 to 74 & perhaps 69. If anyone is interested the syncing directions on p.70 say "If you can't lock orunlock, sync the key or replace the battery p.69." Then one step says UNlock using the key bit... well DOH.. what if it is already unlocked?
There's no mention of which way to turn the key bit to do either, (which would be OK as it is the conventional clockwise-to-lock,) but the key bit can't be turned far enough to do both unless you pull the key out & turn it over.

Removing a battery is fun as there's a springy connection underneath it which causes a little flying saucer effect as it sproings out, possibly never to be found again.

Removing the cap cover to access the keyhole can easily crush a small bone in the tip of your index finger or bugger the distal metacarpophalangeal joint (I had to Google for that term).