28 replies to this topic

[mccand]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Model: Morris Mini
Year:1972

Hi there. My mini has an electrical problem where it is shorting & blowing a fuse. If I pull out the wiper motor plug, it works fine. I tried replacing the infamous "park" switch, but it appears the problem is still occurring (seems to be somewhat intermittent).

I see that no one sells 1-speed motors any more. I have a 1-speed motor, but it is the cylindrical / strap type mount. I also have a 1-speed "rocker" (not toggle) switch.

So my question is, can I get a 2-speed motor & plug it into my 1-speed switch / harness and expect it to work? Would the 1-speed be fast or slow? (or would it blow the motor?

Any other ideas?

Thanks so much.

Cheers!

[mniguy_nz]

I stuffed around with the brushes in my two speed for a while and I think the second faster speed is from the third brush. Mine ran fine with only two brushes so it was effectively single speed. I'm not a hundred percent sure but I think it'd be alright to run a two speed motor

[zef]

I stuffed around with the brushes in my two speed for a while and I think the second faster speed is from the third brush. Mine ran fine with only two brushes so it was effectively single speed. I'm not a hundred percent sure but I think it'd be alright to run a two speed motor

I have a 2 speed motor in a 1 speed switch. Just find the right wires/connectors and plug the switch in to which wires correspond to which speed you like.

[mccand]

OK, sounds like it *can* work. How do you find out which wires are for what? measure resistance or something?

[zef]

OK, sounds like it *can* work. How do you find out which wires are for what? measure resistance or something?

Hate to say I just used trial and error.

[mccand]

OK, new info: I determined that when the switch is turned on, my wiper works fine. When the switch is turned off with the wipers anywhere *except* very near the bottom of the windshield, it also works fine (does not blow fuse). However, when I turn it off with the wipers *right* at the bottom of the windshield, the fuse blows.

I suspect this is related to the wiring of the park switch. As mentioned earlier, my park switch is new, but I am obviously still having some trouble.

How is it supposed to work? Like if you turn it off anywhere, is it supposed to go "home"?

I am thinking of taking my new park switch, and cutting off the little protrusion that I believe gets engaged when wipers are at the bottom (and just dealing with manually "parking" the wipers. Does this seem like a reasonable solution? Other ideas?

Cheers!

[Ethel]

The factory fitted 2 speed motors to single speed wipers at one time - "rationalisation" with other BL models.

There are two (3 with 2 speed wipers) +ve feeds to the motor one is controlled by the wiper switch, when you turn the wipers off you turn the other feed on and the park switch turns it off when the blades are in the right place.

I suspect you've just hooked up the wrong leads out of the motor to the park switch. you could run a wire up from the solenoid to experiment and work out which is which. Unless someone knows the colour codes?

[GraemeC]

Certainly a wiring issue, eather at the switch, the wiper plug or where the park switch connects to the motor wires.

The park switch switches the NLG (Brown with Light Green) wire between 12V and earth - it sounds to me like it is switching the full 12V to earth if it is blowing the fuse.

Let us know the colours from you one speed harness and I will try and tell you which wires they should connect to.

[mccand]

I looked at the wiring. The harness going into the motor has a connector shaped like a large rectangle with notches on one end such that it is thinner at one end (top per figure below). The thin end has one horizontal socket, and the remaining 4 "vertical" sockets are in the larger portion of the rectangle. See "figure" below.

__1__
_| - |_
| |
5| | | |2
| |
4| | | |3
|______|

Assuming we are looking at the *back* of the plug (where the wires go in), the colors of the wires are as follows:

1: Black
2: Brown-light green
3: Green
4: Red- Green
5: (Empty)

I have a hard time imagining these are messed up (since they are built into the harness / connector), and also I doubt that anyone would have messed with the "motor to park switch" wiiring (I matched the existing wiring when I put in the new park switch, and the wipers behaved the same way as they do now before I replaced the park switch; ie it did not self-park).

SO I suspect that the wires to the wiper switch in the dash are not correct. If someone could tell me how those should be wired (ie color of wire to position of pins on back of switch), that might solve my problem!

One other note: I found some exposed copper on both the black wire and the brown - green wire, so this may well be my short problem (added electrical tape to remedy this), but this still does not fix the no self park issue.

Thanks, all, for your assistance! and any insight as to the wiring is also appreciated.

Cheers!

[mccand]

my figure did not come out as I had hoped. But if you imaging a bunch of spaces in the right place (between the |'s on the 2 short rows), I think you'll get it!

[mccand]

This morning I went to look at the switch wiring (the switch in the dash).

It looks like this: (same standard, looking at the BACK of the switch, the side where the wires come out).


_______
| |
| |
| | | 1
| |
| | | |
|______|
3 2


1: Red-Green
2: Green
3: Brown / Green.

probably same caveats apply for misfigured figure, so you'll have to imagine some spaces.

So it looks like:
my 1 from the switch goes to my 4 to the harness
my 2 from the switch goes to my 3 to the harness
my 3 from the switch goes to my 2 to the harness

-using the international mccand figure and numbering standard of course


Thanks so much for your help...

[Ethel]

The wires I was referring to are from the motor brushes to the park switch. Yellow/green is for the fast wipe

http://homepage.ntlw...stler/wiper.pdf

I haven't been through it, but looks well put together.

[GraemeC]

It sounds like the brown/Green is live when it shouldn't be, so when the park switch puts it to earth it blows the fuse.

Do you have a multimeter? If so check the following:
With the wiper swtich OFF and the motor unplugged:
Black = 0V and continuity to earth
Green = 12V
Red/Green = 0V and continuity with Brown/Green
Brown / Green = 0V and continuity with Red/Green

With the wiper swtich ON and the motor unplugged:
Black = 0V and continuity to earth
Green = 12V
Red/Green = 12V and NO continuity with Brown/Green
Brown / Green = 0V and NO continuity with Red/Green

[mccand]

Here are the results:

Everything checked out *except* when the switch is off, it does NOT have continuity between brown/Green and Red/Green! (which indicates to me that at a minimum I will need a new switch that works properly). Anyway...

So I went ahead and jumped them with the switch off, and the wipers came down and stopped at home (good!), but unfortunately the fuse then promptly blew.

Recommendation on next step? I suspect it will involve the wiring to the park switch? I have not pulled it off yet to determine color and position of wires...

Thanks so much!

[mccand]

I just took a look at the wiring to the park switch. The link from Ethel says that "three wires 'can' enter the back of the self park switch. Well, mine has only 2 of them- the blue and the red. No yellow. But the blue and red are in the correct place according to Ethel's pdf.

Do I need a new motor? (in addition to new switch per above)? (back to the original post, a 2-speed would work?)

Thanks!