LUCAS WIPER SWITCH Part No. 35927

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100BUR
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LUCAS WIPER SWITCH Part No. 35927

Post by 100BUR »

Hi All,

Still struggling a bit with the 2 speed wiper motor

Correct toggle switch ordered.... I have checked with DVM does not seem correct to me

There are 5 terminals on the back of the switch with no number identification tags

The switch could have eight terminals but only has 5 have connectors on

Two across the top two at the bottom and four in the middle

Could some one tell me the terminal numbers so I can check again

Looking at the back of the switch the :lol: are the spade connections

:lol: :lol:

:lol:

:lol: :lol:


Thanks

LUCAS WIPER SWITCH Part No. 35927

Terminal Connections
4. 1st speed red/green light
8. Park brown/light green (linked to no.4 when switch is on off position)
6. Ignition live green
2. 2nd Speed blue/light green
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smithyrc30
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Re: LUCAS WIPER SWITCH Part No. 35927

Post by smithyrc30 »

According to the Lucas pin out for a 35927 switch the following connections are made:
Position 0 (off) Pins 1, 2, 6 & 7
Position 1 (slow) Pins 1, 4, 6 & 7
Position 2 (fast) Pins 1, 4, 7 & 8

In order to make the motor work as required you need to connect the switch like this:
In position 0 the slow speed must be connected to the park switch only
In position 1 the slow speed must be connected to the power feed and the park switch and fast speed disconnected
In position 2 the fast speed must be connected to the power feed and the park switch and slow speed disconnected

The only way to wire the 35927 and achieve that is this:
Pin 2 the park switch (connected via the brown/light green to pin 2 on the wiper motor)
Pin 4 the power (connected via the green wire to the ignition feed. Note that the wiper motor must have an ignition feed to pin 4 to make it park)
Pin 6 the slow speed (connected via the red/light green wire to pin 5 on the wiper motor)
Pin 8 the fast speed (connected via the blue/light green wire to pin 3 on the wiper motor)

All of the above assumes that the wiper motor park switch and brush plate are connected correctly and the switch has not been 'helped' internally by someone.....

Which isn't always the case.... :lol:

On the 14W motor there are 3 wires from the brush plate Red, Yellow and Blue.
The Blue is the earth and should be connected to pin 1 on the park switch/connector assembly on the motor
The Yellow is the fast speed and should be connected to pin 3 on the park switch/connector assembly on the motor
The Red is the slow speed and should be connected to pin 5 on the park switch/connector assembly on the motor

You should check that your switch operates as described above with a continuity tester and the the motor is wired correctly otherwise you will be chasing the circuits around for ever.

Good luck!
100BUR
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Location: Cumbria, The lakes, were the roads are always quiet, and the sky is nearly always blue

Re: LUCAS WIPER SWITCH Part No. 35927

Post by 100BUR »

Hi,

Much appreciate the detailed reply advice & encouragement :D

I can not get the switch pin numbers ( That have terminal connection on the back of them) to correspond to the correct connection.

If we assume numbers go left to right ie all odd number on left even on right going down 1-8

I would have the following two combinations depending on which way up I have the switch..

Position One
1,2,3,5,8 Terminal Connections

Position Two
1,4,6,7,8
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smithyrc30
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Re: LUCAS WIPER SWITCH Part No. 35927

Post by smithyrc30 »

Do you have the connections in position 0 (off)?

I presume you list shows the mid position (position 1) for slow speed and bottom position (position 2) for fast speed.

This is a picture robbed from the web showing a reproduction of the 35927.

7 & 8 are the bottom of the switch, 1 & 2 are the top.

Do you have a picture of the switch you have?
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100BUR
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Re: LUCAS WIPER SWITCH Part No. 35927

Post by 100BUR »

Hi Again,

Position 1 & 2 is which way I have the switch up.

Switch was new from Minispares

As you can see from pics it only has five terminals and no number identification

Thanks for all your help
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smithyrc30
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Re: LUCAS WIPER SWITCH Part No. 35927

Post by smithyrc30 »

Ok I see now.

Can you map the pins so we can see which is connected to which in each position of the switch?

If you have a multimeter set it to continuity and wait for the bleeps.

If not a battery a bulb and some wire will do.

To keep it simple let us assume the the dual side by side pins are 7 & 8 and work from there.

If you can tell me which pins are connected to which in each of the 3 switch toggle positions, I'm sure we can tell if the switch will do what you need it to.

It clearly is not a 35927 type switch because it does not have 6 pins on it....
100BUR
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Re: LUCAS WIPER SWITCH Part No. 35927

Post by 100BUR »

Thanks for the replies

Off 1,6,7

Position 1 1,4,6,7

Position 2 1,4,7,8

I have looked again :?

But I can not see in working in all three positions :?
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smithyrc30
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Re: LUCAS WIPER SWITCH Part No. 35927

Post by smithyrc30 »

Hi, the switch you have will not do what you need it to no matter how you wire it up unless you include a relay in the circuit.

The issue is there is no pin pair that is connected in position 0 but not connected in positions 1 & 2.

Sorry, you need a different switch or a relay.
100BUR
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Re: LUCAS WIPER SWITCH Part No. 35927

Post by 100BUR »

Thanks

Just thought it was me being stupid :lol:
madcal
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Re: LUCAS WIPER SWITCH Part No. 35927

Post by madcal »

smithyrc30 wrote: Sat Mar 18, 2017 11:54 pm According to the Lucas pin out for a 35927 switch the following connections are made:
Position 0 (off) Pins 1, 2, 6 & 7
Position 1 (slow) Pins 1, 4, 6 & 7
Position 2 (fast) Pins 1, 4, 7 & 8

In order to make the motor work as required you need to connect the switch like this:
In position 0 the slow speed must be connected to the park switch only
In position 1 the slow speed must be connected to the power feed and the park switch and fast speed disconnected
In position 2 the fast speed must be connected to the power feed and the park switch and slow speed disconnected

The only way to wire the 35927 and achieve that is this:
Pin 2 the park switch (connected via the brown/light green to pin 2 on the wiper motor)
Pin 4 the power (connected via the green wire to the ignition feed. Note that the wiper motor must have an ignition feed to pin 4 to make it park)
Pin 6 the slow speed (connected via the red/light green wire to pin 5 on the wiper motor)
Pin 8 the fast speed (connected via the blue/light green wire to pin 3 on the wiper motor)

All of the above assumes that the wiper motor park switch and brush plate are connected correctly and the switch has not been 'helped' internally by someone.....

Which isn't always the case.... :lol:

On the 14W motor there are 3 wires from the brush plate Red, Yellow and Blue.
The Blue is the earth and should be connected to pin 1 on the park switch/connector assembly on the motor
The Yellow is the fast speed and should be connected to pin 3 on the park switch/connector assembly on the motor
The Red is the slow speed and should be connected to pin 5 on the park switch/connector assembly on the motor

You should check that your switch operates as described above with a continuity tester and the the motor is wired correctly otherwise you will be chasing the circuits around for ever.

Good luck!
Hi,

Bit of a thread resurrection but I found your really helpful post and need similar help.

What I do not understand from your info above is that when the switch is in position 0 (so 1,2,6 & 7 are connected) there is no power going to the wiper motor to power the park switch since pin 4 is not connected.

So how does the motor get the power for park?

Just about to do the wiring on a new two speed motor and new 35927 switch on my series 2a Land Rover.

Thank you
madcal
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Joined: Sun Nov 17, 2024 1:16 pm

Re: LUCAS WIPER SWITCH Part No. 35927

Post by madcal »

Solved it, of course you connect the green wire from the motor to ignition +ve

All works fine, thanks for the help.
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