Xantia IR remote key fob problems

JamesQB · Post by **JamesQB** » 08 Jun 2007, 00:52

Hi,

My 1996 Xantia 1.9TD is experiencing intermittent functioning of the IR remote fob. Sometimes it will lock a few times before just failing to work, other times it will work once and then an attempt straight after will produce nothing and it will stay that way for multiple attempts until later on it'll work again.

Replaced batteries in fob and checked state of the PCB (electronics is my game) but no joy.

A known problem to anyone, with perhaps a solution?

Thanks, James.

citronut · Post by **citronut** » 08 Jun 2007, 08:21

mine is intermitent somtimes and on taking it appart there is a bad solder joint on one of joints to one of the switches, other than that its worth checking and or replacing the batterys and may be clean the conections
regards malcolm

ps.
sorry i did not read all of you post before putting my mouth into gear

jeremy · Post by **jeremy** » 08 Jun 2007, 09:27

The IR ones can be checked to see if they 'flash' with a digital camera (and other similar devices). Haven't tried it - but at least you can find out if it signals every time - which will give you more idea if the fault is on the car or the fob.

Xaccers · Post by **Xaccers** » 08 Jun 2007, 10:12

They also have a red led on the side which activates when the button are pressed to show you it's working.

Mine sometimes stops until I wiggle the battery cover.

jeremy · Post by **jeremy** » 08 Jun 2007, 11:00

I think the red light merely shows that it should be working- not that it actually is.

Xaccers · Post by **Xaccers** » 08 Jun 2007, 11:03

Depends if it's in series with the IR LED or not.

jeremy · Post by **jeremy** » 08 Jun 2007, 14:01

I'd have thought it was unlikely to be in series with the LED. Firstly I doubt if the LED would pass enough current for the IR source - and secondly if its in series - the whole thing would fail if the LED gave out - and of course the converse would be true.

Xaccers · Post by **Xaccers** » 08 Jun 2007, 14:30

Only one way to be sure, get an old one which has a working red LED and detatch the IR LED.
If the red one still works, we know all it signifies is that the red LED works, so then the webcam/digital camera technique needs to be tried.
However, if the red LED stops working, we know it's a good sign to show that the IR LED is working, so no need to get out the cameras

They don't need much current, I use UV ones in series.

rowanmoor · Post by **rowanmoor** » 08 Jun 2007, 17:24

I know for certain that 306 keys can show the red led when the IR one is not operating (guess how). Don't know if the circuit is the same as Xantia though.

AndersDK · Post by **AndersDK** » 08 Jun 2007, 20:43

The IR plipper versions have the indicator LED parallel with the IR led.
The indicator only needs some 5-10mA with a series resistor to indicate, while the IR LED gets the full kick from a charged electrolytic capacitor.
As the IR LED is then operated in the low duty cycle high pulse current mode, it will withstand this appearant abuse despite peak currents in the region of 100mA.
This is to ensure the best transmitting range as possible.

LeeDJC · Post by **LeeDJC** » 12 Jun 2007, 13:32

If you "point and shoot" the plip into a digital camera or webcam you should be able to see the LED come on, if not then it's buggered. If you can, then it's the sensor thats had it.

If it's your plip thats had it, then it's possible to re-program a new one to work with your car.

I've read it on these forums somewhere, something like turn your ignition key to number 2 press the plip etc etc etc

I think a search may be more rewarding than my poor memory!

Xaccers · Post by **Xaccers** » 12 Jun 2007, 13:41

Turn one key in the ignition, and push the open button on the plip while holding it a few cm from the sensor.
Press and hold the button several times (it will go out after each time) and then it will match with the sensor.

I tried this as I had a spare key which wasn't working with the sensor.
Matched it up, and you guessed it, spare key worked, main key no longer did, so plips were actually different! grr

rowanmoor · Post by **rowanmoor** » 13 Jun 2007, 12:28

If it is the same as the 306 then you can do the 2 different keys one after the other and it will remember both.

i.e.
Turn on ignition
Press & hold key 1 a few cm from the sensor
Press & hold key 2 a few cm from the sensor
Turn off ignition

However, you will need a 3rd key to do the ignition part for this.

Xaccers · Post by **Xaccers** » 13 Jun 2007, 13:53

rowanmoor wrote:If it is the same as the 306 then you can do the 2 different keys one after the other and it will remember both.

i.e.
Turn on ignition
Press & hold key 1 a few cm from the sensor
Press & hold key 2 a few cm from the sensor
Turn off ignition

However, you will need a 3rd key to do the ignition part for this.

Cheers for that, I'll dig out all my keys and give it a go, as I have the service key!