406 RCL radio key

I appreciate that the question has probably been dealt with here several
dozen times before, but even after following the stardard advice of
"reprogramme the key", "Replace the batteries", "clean out the key using
liberal applications of electrical contact cleaner" and "attempt obscure
ritual voodoo magic on key", I'm still having really irritating intermittant
problems with the radio remote key on my T-plate 1999 406 1.8LX.

Both the "primary" and "secondard" keys play up in equal measure.
Sometimes they work, sometimes they don't. It doesn't appear to be related
to temperature or humidity - though the keys do tend to be more successful
at a distance of 10-12 feet than anywhere else.

I'm also experiencing what sounds remarkably like an electrical hum
(similar to the noise made by an old amp if left disconnected from an
input with the volume turned up) from around the glovebox area. Searches
on this group suggest that the hum is most likely to be the motor
operating the flaps for switching between fresh and recirc air, however
toggling the switch between recirc and fresh air doesn't seem to have a
noticeable effect on the volume or the tone of said hum. This hum is also
intermittant.

Might I just have a loose connection somewhere?

The 406 is a pleasure to drive. Sticks to the road like toffee to
dentures. It's just getting a little embarassing to have to walk back to
my car shouting "WHY WON'T YOU JUST WORK YOU LITTLE BASTARD!?" at the
key at 60% of the time, and a little annoying to have to have the stereo
on drowning out the sound of the hum.

Any hints would be welcomed.

John

 

Replace the surface mounted click button switch on the circuit board in
the key fob. Cost 30p. Difficult (more fiddley) if you haven't done it
before. Or get some one to do it for you.

I'm told the moisture in sweat while the key is in your pocket attacks
the contacts in the click button. Or if you forget and take them diving
to 25 meters by mistake.

Fixed both my keys this way and they now work every time.

 

Fantastic.

I happen to work for an electronics company with an entire factory unit
devoted to surface mount manufacture & servicing.

I'm sure I'll be able to find someone to do it for me for the price of a
beer!

Sounds quite likely.

Would this problem be likely to be the culprit if the little red LEDs are
lighting up on the keypress?

I'll certainly give it a go.

Thanks for the help.

John

 

From what I can work out the click button provides the power line to the
system which triggers the radio pulse. The bad contacts restrict the
current flow and hence although the led lights up there is insufficient
power to transmit the signal.

That my take on it