Chimaera wiper park switch -- high rate of attrition

[PhysDoc]

Hi,

I fitted a new wiper motor park switch in May last year, then again in January this year, and now it has failed again. So this will be the 3rd it's had in under a year. Is it known for them to have such a high failure rate? It is definitely the switch at fault as it works fine in continuous mode, but stops in the middle of the windscreen when you switch it off or put it in intermittent.

The car has been sat unused outside for the last 6 weeks, so it will have been immersed in water and snow, but even so the new switch is not even two months old.

Have I just been unlucky, or could the motor be on its way out, and burning out the switch prematurely?

[Penelope Stopit]

Something is damaging the park switches and as you have mentioned there is a very good chance that the motor is drawing too much current through the park switch contacts, this doesn't mean that the motor is on its way out although it may be, a tight wiper mechanism will also make the motor work harder and draw too much current, you will need to check the mechanics of the wiper system. Unfortunately in many cases where a tight mechanism is found the motor is also found to have been damaged

If you have one of the park switches that you replaced you can open it up and inspect the condition of its contacts, you will very likely see melted plastic close to them or burnt contact faces due to over-current

[PhysDoc]

Hi,

There was no melted plastic on the last one, and the wiper mechanism was free when I changed it last year (though could have since seized -- I shall check tomorrow).

When I changed it last May, the pinion wheel was well seized, so I pulled it out, cleaned it up and greased it.

[PhysDoc]

PhysDoc said:

Hi,

There was no melted plastic on the last one, and the wiper mechanism was free when I changed it last year (though could have since seized -- I shall check tomorrow). The contacts did look a bit burned.

When I changed it last May, the pinion wheel was well seized, so I pulled it out, cleaned it up and greased it.

[Penelope Stopit]

PhysDoc said:

Hi,

There was no melted plastic on the last one, and the wiper mechanism was free when I changed it last year (though could have since seized -- I shall check tomorrow).

When I changed it last May, the pinion wheel was well seized, so I pulled it out, cleaned it up and greased it.

Hello.
The motor may well have been damaged when the gear was getting tight before seizing, strip the motor down, take a good look at the armature windings to see if it's overheated (windings will have changed to a blackish colour if burnt) also smell the armature windings for burning.
You could also test for how much current the motor draws on 1st and 2nd speeds but would need someone here to carry out the same test on their good system so as to be able to get the current draws of a good system to compare yours to
If someone is prepared to get you the current consumption figures, ask for wet screen current consumption