baffled now (it does not take much!)

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stuffedpike20
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baffled now (it does not take much!)

Post by stuffedpike20 »

To explain simply, when I flip the switch to turn side lights on, the wiper motor comes on, even with the ignition off.
I swopped the green wires on the light switch, and wiper switch, thinking that they must be wrong, but this was not the problem.
I have tried 2 different ignition switches, one of them new, and this is also not the problem.
To make things even more complicated, sometimes everything works fine!

Any ideas?

Thanks.
John.
cLunK
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Re: baffled now (it does not take much!)

Post by cLunK »

Well, until someone with more knowledge than I comes along,

Sounds like a short somewhere possibly on the voltage regulator/stabiliser.

Check any cabling going thru the bulkhead etc for chafing

Intermittent usually means something is vibrating and rubbing thru IMHO

A cheap test meter is well worth the outlay if you don't already have one. Just be methodical when testing circuits

Hope that helps

Andy
JOWETTJAVELIN
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Re: baffled now (it does not take much!)

Post by JOWETTJAVELIN »

the wiper motor is being false feeded. Start by going back to basis with the correct wiring diagram for your car. Examine the wiring carefully - insulation could have worn through on both wires and the conductors touching together.
stuffedpike20
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Re: baffled now (it does not take much!)

Post by stuffedpike20 »

Thanks both.
I have got a multimeter and wiring diagram, The wiring all looks good.
Looking at the wiring diagram, it should be impossible to turn on the wiper motor with the light switch I think, and yet.....

Whilst fiddling this morning I managed to have the wiper motor running with the ignition off, and the wiper switch in the 'off' position. Turning the switch to the 'on' position turned the wiper motor off! Also, the side lights were on although the light switch was off.

Faulty voltage stabiliser, or voltage regulator?

I have no idea what is going on, there is a nasty Gremlin in the works.
cLunK
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Re: baffled now (it does not take much!)

Post by cLunK »

Hmmm, strange to say the least.

As you have changed the ignition switch I'd start looking at the area behind the Speedo, as this is where it's more likely to have moved any wiring.

Easy to dislodge something when refitting
StillGotMy1stCar
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Re: baffled now (it does not take much!)

Post by StillGotMy1stCar »

The wiper motor gets a 12V supply from ignition switch, the motor works by switching the earth via the dash switch and park switch, i think this earth is at the regulator control E terminal.
My thought is for some reason this earth is above ground, may be just a poor earth, measure the voltage between E on the control box and the car earth (battery earth terminal) and see if it has voltage when the motor starts. I’m not sure how the control box gets it’s earth, I don't think it's the mounting screws, it might be the earth wire on the P-clip on the bulkhead about 12 inches below where the main loom goes through the bulkhead.

Good luck.

Regards John
stuffedpike20
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Re: baffled now (it does not take much!)

Post by stuffedpike20 »

I think it gets earthed through the wire on the bolt that the flasher unit is mounted on.

I think the wiper motor, wiper motor switch or wiper motor wiring is to blame. When the connections are pulled from the wiper motor, things seem to be OK.
stuffedpike20
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Re: baffled now (it does not take much!)

Post by stuffedpike20 »

Just had a look at some previous posts, and think that the problem lies in the self parking function of the wiper motor.
Will take the lid off and clean the contact ring today.

Thanks for the replies.

John.
StillGotMy1stCar
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Re: baffled now (it does not take much!)

Post by StillGotMy1stCar »

My immediate thought to make the wiper motor start with the ignition off would be to put a supply on the earth lead, the new earth return in fault condition being via the coil and/or fuel pump depending on the distributor and fuel pump contacts being open or closed.
Turning the wiper switch on in fault condition stopping the wiper further suggests a supply on the earth lead instead of an earth, acting like a more conventional supply switch.
I am assuming your car has standard wiring and wiper motor, where the motor is fed with a supply from the ignition circuit and the wiper switch and self park is in the earth.
That is what takes me to the E terminal on the control box as I believe that is the wiper earth wire and a handy thing to check first.

Cleaning the self park switch won’t do a thing for the wipers starting with ignition OFF, but the wire that comes out of the wiper motor and goes to self park contact has a rubber insulation that gets brittle with age, if the inner of that wire touches the case it will start the wipers with the ignition ON.

Regards John
stuffedpike20
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Re: baffled now (it does not take much!)

Post by stuffedpike20 »

Thanks all.

Sorted out now.
A combination of things as usual.

Faulty ignition switch
Me confusing the wiper motor with the wiper motor switch on the wiring diagram
Me therefore adding an extra wire to the wiper motor switch ( I thought it was a green wire, but it was a red lighting wire...colour blind )
The Haynes manual wiring diagram being wrong... the white and red wire go to 3 on the ignition switch, not 1

Cleaned up the wiper motor, and now it even self parks.

Going to the bottom of the stairs to sit and think about what I did. :roll:

Thanks. John.
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