Weird C5 electrical gremlins

[Johnno]

Hi guys. I've been having some odd issues and would appreciate some feedback before using the toolkit. It mostly concerns the auto wipe function (which, frankly, I've never liked anyway) and the aircon.

The auto wipe seems to be stuck on single-speed intermittment and will operate even when the screen is dry. Is the controller within the mirror housing at the top of the screen? Given that the speed is constant, I'm not immediately suspecting the sensor, although it may have been bypassed by the previous owner due to a fault.

With regard to the aircon, it works but I note that the fans come on full-speed when the button is pressed - is this normal? I seem to recall that my previous C5 used low speed at those times, tho' that may be false memory. I've tracked down a wiring diagram / diagnostic but, assuming I've deciphered the Frenglish correctly (it rather puts one in mind of those early Japanese motorcycle manuals!), the suggestion is that the fans respond according to the system pressure and internal temperature with any of low / medium / high speed. Now, the weird bit is that several times recently the central display has gone blank, the radio has gone off and the display then re-boots with the aircon on! No action on my part so I guess it must be just the deus ex machina.

The other annoying thing is on start-up, when the display tells me for around 25 seconds that none of the rear passenger seatbelts is fastened - like I didn't know that. Is that usual? Not that it's vitally important, just irritating.

As I say, I'm intent on getting stuck in, probably when I change the passenger side flap-control motor soon, but would appreciate any pointers.

Enjoy the summer, such as it is!

[SaabC5]

Seat belt warning light is usually only on the front 2 seats.

If you don't like the autowipe function then just leave the stalk in the middle and turn them on/off manually. The sensor is indeed the "bubble" you can see in the screen infront of the rear view mirror. If the screen has been replaced at some point chances are the sensor hasn't been sealed in properly hence the playing up.

[Johnno]

Thanks for the reply Saab. Definitely have the warning on the rear seats (it's the VTX + optional extra?). I do think the screen has been replaced and I did wonder if that meant that the sensor wasn't getting the right info. But would that cause the effect of having the wipers operate on auto even in dry weather?

I often just use the flick-wipe function, as I found on the previous car that the wipers were ok in good, solid rain, but anything light had them apparently unsure how to respond.

[myglaren]

The screen in the area of the sensor needs to be cleaner than a clean thing for the auto-wipe to function properly.
You can turn the auto-wipe off and just have intermittent if you prefer.

[Clogzz]

You can turn the auto-wipe off and just have intermittent if you prefer.

How do you do that ?

[myglaren]

You can turn the auto-wipe off and just have intermittent if you prefer.

How do you do that ?

Now there's a question.
It wouldn't work on my old C5. Button on the stalk was duff as was the sensor.
Works on the new one and there is presumably a method in the menu but I let my handbook go with the old car and there isn't one with the new car.
I have handbook scans on my other computer which unfortunately is somewhat cabbaged but will have a look when possible.

[wheeler]

The other annoying thing is on start-up, when the display tells me for around 25 seconds that none of the rear passenger seatbelts is fastened - like I didn't know that. Is that usual? Not that it's vitally important, just irritating.

Is this a MK 2 C5 as i've never seen a MK 1 with rear seatbels warnings ? Anyway, I believe this is correct operation of the warning system, It has a really strange operating principal & it's to do with the rear seats dont have bum sensors, only the fron passangers has this.
If it's really irritating I suppose you could just leave the buckles plugged in at the back ??

[JohnD]

The other annoying thing is on start-up, when the display tells me for around 25 seconds that none of the rear passenger seatbelts is fastened -

!

Probably normal C5. Mine does the same - inspite of having the seats always folded flat

[Clogzz]

handbook scans

Nothing of use in my book.

[myglaren]

I did manage to find that but it took two hours to get there.
I think there must be an option on the infoscreen menu to turn it off but never got to that part of the handbook, gave it up as it was taking up to ten minutes to load each page.

There are some odd things that come up on the infoscreen - "Programming" is one, then there is something else rather obscure.
I have a feeling I turned autowipe on on the infoscreen but haven't worked out how to turn it back off again. It is OK now but was a nightmare until I got the screen cleanish - there still seems to be some residue of something on it, Rain-X I presume.

I keep meaning to have a fiddle around with it but forget if it isn't anything urgent.

[Citroenmad]

If there is a fault with the wiper sensor then the auto function reverts back to a standard intermittent wipe, which yours has by the sounds of it. There is no easy way to disable the auto wipers and have intermittent, possibly through a Lexia, ive not looked.

[Clogzz]

Thank you both, and sorry Steve for the time and trouble you went to.

The ‘programming’ display is to set the over-speed warning.
The other thing is ‘check control’ … not much use because it tells us what faults it displays at start-up.

The book does list the display of ‘automatic wiping active’ but nothing about how to change it.
It looks like it will have to stay as it is for now, and there’s light rain forecast for tomorrow.

[myglaren]

You could disconnect the sensor and it should default to intermittent wipe.