Wiper problem C5 Mk2

[Wideboy]

Hi all,

Long time lurker...thought it about time i posted.
(Nothing to do with the fact i have a problem of course )

Anyway...The main annoyance is when the car has been left for a while,on return to it,a press on the remote sometimes starts the wipers going and the only way to turn them off is to insert the key and turn on the ignition.They don't autopark,they just stay where they were when the ignition happened to be switched on.Same when driving,any use of them results in them stopping when they want to.To get them out the way requires a few presses of the down sweep arm until they happen to stop out of the way.Sometimes even opening any of the doors has the same effect of setting the wipers off too.
Noticed also that i have no sidelights.The dash lights up but no sidelights although the rears are on.Hoping just bulbs but not sure if linked to wipers somehow.
From reading various posts i initially thought the the Comms unit might be the culprit and had a word with a Citroen specialist.He said it may very well be that but could also be the Bsi/Vsi? Don't really want to replace both of them for the sake of wipers but it is very annoying!
Tried a reset procedure a couple of times,still the same but that might be me being thick and not doing it right!

Any help appreciated.

Cheers,

[Trainman]

Noticed also that i have no sidelights.

The C5 II is notrious for blowing the front sidelights, I got to the point of almost changing mine weekly, there is a post somewhere about changing them for LED's

i initially thought the the Comms unit might be the culprit and had a word with a Citroën specialist.

Again another common issue, they are well known for causing problem's everything from the indicators and/or lights suddenly coming on to wiper working or not for no reason. I'd be tempted to try the Comms unit first.

[cachaciero]

BSI / motor assembly but best to check a few things with a Lexia.

Why BSI? well the comms unit "only" processes switch positions which then get sent to the BSI which actually drives the wiper motor.

It appears that switch commands are being sent so it is either the logic in the BSI or wiper motor i.e whatever device it uses for telling the BSI where it is that isn't working.

Thinking about this it may not be the BSI but the engine relay unit, I'm not clear if there is any intelligence in the engine relay unit or if it's just relays controlled by the BSI.

EDIT

The fact that the wipers get triggered when opening the doors is also a pointer to the BSI as doors and locks get driven from the BSI.

Bad power to BSI may cause this, disconnect battery, reseat all connectors in to the BSI reconnect battery and see how it goes.

cachaciero

[Wideboy]

Noticed also that i have no sidelights.

The C5 II is notrious for blowing the front sidelights, I got to the point of almost changing mine weekly, there is a post somewhere about changing them for LED's

i initially thought the the Comms unit might be the culprit and had a word with a Citroën specialist.

Again another common issue, they are well known for causing problem's everything from the indicators and/or lights suddenly coming on to wiper working or not for no reason. I'd be tempted to try the Comms unit first.

Thanks Trainman. Actually having read that i do remember reading somewhere about LED's for sidelights so that would be a good road to go down.

BSI / motor assembly but best to check a few things with a Lexia.

Why BSI? well the comms unit "only" processes switch positions which then get sent to the BSI which actually drives the wiper motor.

It appears that switch commands are being sent so it is either the logic in the BSI or wiper motor i.e whatever device it uses for telling the BSI where it is that isn't working.

Thinking about this it may not be the BSI but the engine relay unit, I'm not clear if there is any intelligence in the engine relay unit or if it's just relays controlled by the BSI.

EDIT

The fact that the wipers get triggered when opening the doors is also a pointer to the BSI as doors and locks get driven from the BSI.

Bad power to BSI may cause this, disconnect battery, reseat all connectors in to the BSI reconnect battery and see how it goes.

cachaciero

However...i'm more inclined to go with Cachacieros suggestion for no other reason than gut feeling.I would be pleasantly surprised if it was only a relay but having owned many Xantias and C5s over the years i know things are rarely that simple!

When driving the car the wipers always play up. i.e they work when signalled to,the problem is when you come to stop them.They eventually do but wherever they feel like it.For instance,pressing the stalk down for a single wipe results in 5 or 6 and where they eventually stop is anyones guess.It's just a matter of repeating the process until they stop out of the way.

The engine can be shut down,key removed and locked and gone back to within a minute or so and behave as it should, i.e neither the remote or the opening of the doors triggers the wipers (although operation from the stalk still results in the problems mentioned).Leave this for any longer and thats when the problems start again..as soon as remote is used to unlock the car the wipers start and only shut off when key inserted and ignition turned on.

Many thanks for your replies so far,all opinions appreciated.

[cachaciero]

When driving the car the wipers always play up. i.e they work when signalled to,the problem is when you come to stop them.They eventually do but wherever they feel like it.For instance,pressing the stalk down for a single wipe results in 5 or 6 and where they eventually stop is anyones guess.It's just a matter of repeating the process until they stop out of the way.

You may have two problems One thing that is consistent in your problem is that the wipers do not park correctly.

The wiper motor assembly has a "park" switch now either this switch is not working or it is working and the signal is not getting into the BSI or the BSI is getting the signal and not processing it correctly.

Resolving this problem may or may not resolve the issue of sporadic triggering of wipers by other things.

cachaciero

[Wideboy]

Update.........

Been to my usual very good independent today and his instinct is to try a comms unit first.He has an unused one lying around that he was willing to try on my car but.....
I'm sure i read somewhere that the comms unit doesn't have to be coded to car UNLESS it has esp or cruise control.My car has both so i mentioned this to him and understandably he was then a little unsure! He then metioned something about 'planet' which i'm guessing is the Peugeot software and hinted that by using that we could effectively tell the car it doesn't have either esp/cruise and thus be able to try his comms unit.
He's actually trying it this way to save me money because obviously i dont want to pay for a comms and then find it was the bsi and have to change that too.He also mentioned he may be able to do the same with the rain sensor in order to rule that out too.
The battery has been changed so we can rule out voltage irregularities and sidelights replaced (was just bulbs!).
On a different tak,does anyone know a good source for the undertray and o/s wheel liner for a mk2..none on ebay and none in local scrappies.Don't really want to be paying stealers £120 for 2 bits of plastic!

[Citroenmad]

The comms unit does need to be coded in with your car having ESP, im not sure if it is effected by having cruise or not. If your car is H3+ then it would also need coding, as the steering angle sensor will be different.

Its worth a try since you have acess to another comms unit.

[cachaciero]

Maybe I'm being a little pedantic here but my interpretation of "coding to the car" is when the unit under question gets software downloaded to it which then ties it to a specific car e.g VIN Codes. On the C5 the only units I know of which are affected by this is the BSI, Injection ECU and the BHI all of which are hard coded in "one time programmable ROM". The radio is also coded to the VIN number but this can be changed using a Lexia

The Comms unit as far as I know doesn't need any of this, and with the exception of the steering wheel position sensor is electronically a relatively simple unit doing nothing more than reading switch conditions and encoding the switch data onto the CAN bus on S2 cars. However on ESP cars the steering sensor does need to be calibrated using a Lexia.

EDIT
The COMMS unit is a physically different item depending on whether the car has ESP or not at least on S1 cars.

I will still stick with what I said earlier this problem is not the comms unit it's either the motor parking switch the BSI or wiring between the two. If the wipers didn't run when selected then the COMMS unit might be a suspect but they do and they stop when selected off, just is not in the right place, ergo the right data is being sent from the comms unit but stop position synchronisation is done by the motor and BSI not the COMMS unit.

cachaciero

[wheeler]

The cruise control has no programing in the comm's unit & as far as the ESP is concerned it's not actually programmed to the car you actually just calibrate the steering angle sensor so nothing that is'nt reversible.

[Wideboy]

Update....

Sorry for the delay in posting but numerous trips to my indy hadn't improved matters so nothing to report.
Basically he tried a new comms which didn't solve the problem but also noticed that while the comms was totally removed the wipers started again when he opened any of the doors..very strange.
Anyway,bit the bullet and booked it into the local main dealers for tomorrow..BUT..having been up to it's usual tricks this morning i left it for a while and upon going back to it i noticed that the wipers didn't immediately start when i pushed the button to unlock the car.On top of that the wipers behaved impeccably in every position as if nothing had been wrong at all.They've been like this all day but obviously i know that as quick as they have (unexpectedly) started working they could revert back to being troublesome.
It has got me wondering though..they can work normally and park in the right position when they want to so to me this would rule out a faulty wiper motor assembly and i'd love to think that a bsi change wouldn't be necessary or am i clutching at straws? Also wondered whether it could be something as simple as a dodgy earth or similar...seems weird that they've started working during the wettest weather we've had round here in years.
Would love to put this to bed but as with most of my Citroens this problem is just the tip of a rather big iceberg.

[Trainman]

seems weird that they've started working during the wettest weather we've had round here in years.

Ah! The wonderful world known as 'citroening'

[cachaciero]

Update....


Would love to put this to bed but as with most of my Citroëns this problem is just the tip of a rather big iceberg.

I think anybody with a C5 can empathise with that statement

cachaciero

[citronut]

maybe your indy has reset some relative software either with or without knowing,

regards malcolm