replacement IR roof sensor for 306 XSi

Hi all
I have a '96 306 XSi. My plip remotes have had the dreaded
'battery rundown' fault ... however I *may* have fixed this (more
details if I get the whole thing working).

However in the meantime I suspect the IR sensor in the roof has died.
I've had a leak from the sunroof which I've been negectful of. So when
I try to re-program the Plip, nothing happens. I've had a look at the
sensor in the roof and it's clearly suffered from water damage. I have
an electronics background and will have a go at fixing it, but that's
a long shot.

So, a couple of things:

- where to get a new roof sensor from - any idea what they are
properly called?

- Is this sensor linked to th Plip - ie. if I were to get a
replacement roof sensor, would this work with my current Plips once re-
programmed?

Obviously I am also looking into fixing my sunroof leak...

thanks
jon N

 

Jon.
I cant help with your sensor problem, but I had a leaking sun roof, it
turned out to be the drain holes were blocked, I cleared them with a wire
coat hanger.

Bryan

 

Hi Bryan
Thanks for your message. i've been having a look for the drain
holes after reading back old messages on this group. Can you advise
where they are - I can't see them yet?!

Thanks
Jon

 

Hi Jon.
They are in the corners at the front, if you can't see them I would think
that they are full of muck and need to be scraped out.

Bryan

 

I got hold of a spare plip key for my wife's 306 and that programmed ok.
It's now gone the way of the other two though with dead batteries after a
couple of weeks so if you do find the answer to that one I shall certainly
be interested.

 

Hi Keith

Thanks - actually that's a good point (about spare plips working) now
that I think of it.

I 'fixed' the plip by replacing the capacitor, which I'd heard might
be faulty. It did look as though it might have been ... electrolytic
capacitors can 'burst' and the ones on my plips do show some of the
symptoms. I'll see how long the batteries last before posting full
details ... and obviously I'd rather prove the whole system first...

Regards
Jon N

 

I shall wait with all fingers crossed. tyhis nmay asfffect mny typimng
;o)

 

;-)

It also looks like the roof receiver is not tied to the Plip. For
those of a technical bent ... the Receiver PCB in the roof only
contains a set of Infra-red sensors, and an amplifier chip, together
with a few other parts. The decoding part must be elsewhere (any clues
anyone?).

Cheers
Jon N

 

I have had exactly the same problem with the receiver due to water through
the sunroof.
I took the receiver board out and cleaned all the corrosion fur off very
carefully, particularly where it bridged any printed circuit conductors. I
then sprayed it with electrolube to keep it water repellent, and in my case
it then worked OK. Worth a try in yoyur case too i would think.
Now to have a look at the plip, which is also running down batteries in no
time.
I checked the little switch inside, and it now never seems to be open
circuit, there is always a resisance of 100 ohms or so, which is what I
assume to be the cause of the batteries not lasting. Though whether it is
the switch or the electrolytic I do not know.

 

ECU? The post from Brian looks interesting, yours might be fixed the same
way.

Keith

 

Hi Brian

That's the sort of thing I am doing. There is actually one track which
is damaged; I have repaired that without success. But I have also
found the data sheet for the chip used, so I can probably work out
what is & is not happening. Sometime being quite technical is a bit
tedious... I will keep you informed...

seemed to be acting fine. I've heard a few stories about the plip
(apart from the 'They stop working' one):

- there's a short on the PCB. Plausible but unlikely IMHO
- some mechanical problem causing the batteries to be loose, or
something. Not in my case
- it's a capacitor ... plausible in my case ...

.... although I wonder why in the case of both plips the batteries only
started failing after I changed them. Maybe the slightly higher
voltage of the fresh batteries did the capacitor in???

I've also wondered about a failure of the plip semiconductor over
time ... but have no evidence of this.

On the sunroof front, I've found the drains and shoved a couple of
feet of wire down them to clean them. Any idea where they come out, I
can't tell if I've done this properly?

Cheers
Jon N

 

They come out at the bottom of the A pillar. Just run some water
gently down the tubes.

 

This may be completely unrelated, but as you mentioned capacitors
bursting it may be interesting reading:-
http://en.wikipedia.org/wiki/Capacitor_plague

Matt

 

Hi Nigel

[...]

Thanks ... I was being a bit idel to write before checking ... I've
done this & all looks good ;-)

J

 

Hi Matt

[...]

Thanks - I know about this (I'm an electronics engineer in another
life) and it may well be related. I've mended PC motherboards by
replacing capacitors like this in the past. I wasn't expecting this on
the plip because (a) the timescale is different - mid-90's rather than
early 2000's, and (b) the bulge on the capacitors I've seen is quite
slight, much less than eg. the pictures in the wikipedia article.

I will post a picture of the caps when I get chance, and if I show
that this fixes the problem. Notwithstanding my IR receiver problem,
with the replacement cap. my plip *seems* to have been working (ie.
the red LED flashes on when I press the button) for several days now,
which is more than used to be the case.

HTH
jon