Wiper has started working on it's own

[Chuduc]

Hi, I have a 'C250 ELEGANCE TD AUTO 1996 Estate' and have recently started having a problem with the wiper/indicator combination stalk. It started a couple of months ago when every so often the wiper would do 1 'sweep' when I indicated left...not every time though. Then it started doing it sometimes when I indicated right, and now does it whenever it feels like it...irrespective of whether I've indicated.

I don't think I'm alone in this problem and would realy apprciate any advice. Is the common opinion that this is definitely a problem with the combination stalk? Or could i be down to the wiper relay? If it needs a replacement stalk is it an easy task to replace? I understand that the steering wheel would need to come off and I've got limited tools.

If I need to take it to a garage would I be better off sourcing the part myself and taking it to a garage.

As I said opinions and advice would be greatly appreciated.

Charlie

 

[Dec]

Have a look at page 1 and 2 of …this thread… It would seem there is a fault in the twisting part of the stalk, something loose or shorting when you handle the upper part of the stalk when indicating.

Try using the lower part of the stalk, to indicate, to avoid the problem until you get it fixed? Or replaced?
I just took my own stalk apart last week, nothing wrong with it, just out of curiosity. I would suggest you do the same.

The stalk or combination switches are two separate switches in one, the rotating section controls the wiper/washer. The whole stalk itself is a lever switch for head light/ head light flasher and up/down for indicators. A fault in either function usually requires a replacement stalk, this involves the removal of the air bag and steering wheel.

Where there is a fault in the wiper system, removal of the tip of the stalk to inspect the switch mechanism, particularly the underside, can reveal possible faults or evidence of burning, if there is no evidence of any damage or faults, then spraying the contacts with switch cleaner, equipped with a straw attachment, can sometimes solve the problem. This is the best thing to try first.

As the switch mechanism itself is enclosed, it is not practical to dismantle it. It is only possible to spray into a limited number of openings on the outside of the switch mechanism. Precautions should be taken to protect the surrounding area from over spray of the switch cleaner chemical spray. The chemical can smudge/damage Vinyl and any painted symbols on the stalk and surrounding area.

Turn the steering wheel for a better view of the stalk. With the ignition off, rotate the wiper switch to position lll, in this position any possible scars you might inflict on the switch in the process of dismantling will be hidden to some degree.

The way to remove the tip of the stalk is with a firm thumb grip, a piece of dry rubber will help your grip, don’t use any griping tools or you will damage the soft plastic, use the blunt side of a thin knife (wraped in a handkerchief) to lever gently, side to side while you wrestle the tip off. Expect to spend 5 minutes at this, it is a very tight fit, but it will come off with patience and persistence.
A small plunger and a spring will shoot out when the tip finally pops off.

Test the function of the switch by moving the peg to the 0-l-ll-lll position. The wiper can be run using the peg to switch to different settings. The stalk could be left unassembled while the car is driven for a few days if it was beneficial towards tracing an intermittent fault, the windscreen washer pump function won’t work, while the tip cap is off. Cover with a small transparent bag to protect the switch and prevent the loss of the peg, which can move from its position within the switch.

Check both channels inside the “square” section (Pic 2) for signs of damage or wear.

When the end of the stalk is pushed in the plunger touches the 2 end of stalk contacts, operating the washer pump and the treble sweep action of the wiper blade.

When reassembling, move the peg to 0 position, ensure the peg, (which protrudes from both sides of the switch) engages with the two slots (second picture, the slots move the peg when the stalk is rotated) inside the “square” outer casing and make sure the whit arrow is pointing to the 0 setting mark (Pic 4) on the outside of the stalk. Finally, insert the spring, followed by the plunger, the end tip is pushed back on, a click will be heard when the engage.
You will notice a “long spike” at the end of the “square” outer casing, this is to guide the end cap on.

When assembled, the peg moves the inner “barrel” of the switch mechanism to positions 0-l-ll-lll when the “square” outer casing (with symbols) is rotated.

Dec

 

[Dec]

Continued
Dec

 

[torquewrench]

Thank you so much Dec, that is very useful information, and well illustrated. regs torqewrench.