MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Wipers

Hi there,
Wipers not working at the moment.

I'm not sure how this all works so please excuse me if i sound like an idiot!

1. The big roundy metal thing with a long arm coming from it is the motor right?

2. It has a connector with four wires

Brown - Is this +12V?

Black - Is this ground?

Green/White wire - this goes to wiper switch?

Green/Red wire - this returns from switch?

I took a wire straight from the battery to the Green/White wire terminal on the switch and the wipers worked
so I'm assuming a problem with the wire feeding the switch from the motor connector?

I could be all wrong about this so please put me right on it if I am.

A lot of additions have been made to the car over the years so wiring color codes could be a little unusual!
W Headon

bit more info required - model year, 2 speed or single, are the wipers parked, have you checked the in-line fuse

on my 1973 RWA:

. white/green from ignition switch to in-line fuse

. green/pink from in-line fuse to double connector - which has one green/pink to wiper switch and other to wiper motor

. brown/light green between switch and motor

. red/light green between switch and motor

so no brown as such

bear in mind you need power at switch and motor to park the wipers

Nigel Atkins

ETA: (black is earth)
Nigel Atkins

The motor is obviously OK so first check fuses and then if they are OK check the switch by bypassing it (link the two wires together).

Trev
T Mason

Thanks for the replies.
I never actually used the wipers before!! I never bring the car out in the rain.
I checked the inline fuse - OK
Linked both switch wires - Nothing
Took a wire straight from battery to switch -wipers worked when switch pressed in fully pressed.

Not sure about 1 or 2 speed. Well, Only one speed working, The switch has three positions Off , pressed half way, fully pressed if this makes sense.

I don't think I understand the wiring properly. Can anyone explain

The four wires at the motor connector?

Green/White?

Red/Green?

Brown?

Black?
W Headon

W,
that could be part of the problem not using them will cause the thing to stiffen and fur up (same with heater motor, horns, lights, engine, brakes, tyres ...)

if the switch goes halfway it's either broken or a two speed switch

just a thought, you have to have the ignition on to work the wiper motor - so with your test from battery you bypassed the ignition switch as well as fused supply

I know far too little about the subject to advise you but know that the model and what year your car is would be useful

I've just had a look at my car (note the wiring loom isn't original) it has at the motor -
. green/white
. brown/light green
. red/light green
. black
(these are in a plug that goes into the motor socket)

at single speed switch -
. green/white
. brown/light green
. red/light green

at in-line fuse -
. green/white
. white/green

as I’ve just posted this on another thread I’ll put it here for your consideration too –
just for your info - if you want to, you can add your car details so you don’t have to remember to put in the posts which model or other details

you can put up your ‘Vehicle profile’ and photo too if you want to – easiest way to do this is click on the ‘View vehicle profile’ of someone else (like mine) then scroll to the bottom of the page you’re taken to and follow the one sentence instruction at bottom of page
Nigel Atkins

"I never actually used the wipers before!! I never bring the car out in the rain."

Funny that. BMC designed it to be used in the rain. You can tell, ----- they fitted wipers ;)
Lawrence Slater

Sorry to hijack this thread - but my wipers are playing up too. Recently when I switch them off they don't return to the down position but stay fully up. I have to time when to switch off the wipers quite well to not block the screen. What could this be? I didn't think the wiring was that advanced... so what makes it return? The motor?
C L Carter

I have the 2 speed switch on my 79 model, and an original wiring loom =) so i'll have a look at mine when i get home - might be more useful than Nigel's random wires!
C L Carter

Christian,

luxery is self parking wipers, not all cars had them back in the day

you'll get used to skill and joy of timing your switch off to leave the wiper at the start of their cycle

in the motor is switch that's activated by a sloped block on the bottom of the motor's gear

the dash switch and motor are wired to allow for parking

so it's check all your wires and connections are clean, secure and protected

you could even take the switch out and apart to check it

if the wuiper were working correctly and parking before then note which wres go to which connectors on the dash switch
Nigel Atkins

missed your last post C L

the switch I meant you could take apart is the dash one

if you do just want's required to sort this one problem it will solve only this one problem but if you check the lot of wires and connectors you'll soon see if it's worth continuing and you could be preventing future problems

the randomness of wires is because I don't have an original loom and don't know the age of W's car

as you know if you look in the relevant Driver's Handbook you'll find a wiring diagram :p
Nigel Atkins

If your wipers do not self park, then the fault is in a switch located inside of the motor called the parking switch, and is readily available, as they do wear out.

Sometimes, simply cleaning and reinstalling it is enough to restore self-park-ability.

The switch works like this: after you turn off the power, this switch continues to provide power to the armature until the crank wheel reaches a pre-determined point (the parking position), and then it disconnects the power. Modern wiper motors work the same way (it is very cheap, and effective).

item #38 in this link:

http://www.moss-europe.co.uk/Shop/ViewProducts.aspx?PlateIndexID=1367


Norm
Norm Kerr

Looks like my thread has turned into a "my wipers won't park" issue
instead of a "my wipers won't work issue"!
W Headon

WH, does your heater fan work?
Typically, the wiper motor and the heater fan are supplied by the same fused supply. Switch on the heater fan, if it isn't working either then it is almost certainly just the fuse.

It is an in line fuse fitted in one of those white plastic torpedo holders in the wiring loom somewhere close to the 4 - fuse block. Close to the brake and clutch reservoirs.

Often the fuse just needs removing and the ends wiping clean.
Guy W

W,
help us to help you

what year is your car?

what other checks than you've already put have you made?

what checks did you make on the in-line fuse? (a visual check is not enough)

you checked the wiper motor works so you know that the problem will be in the power supply chain to it

as you don't use the wipers just turning the dash switch on and off a good few times (with the ignitionoff) may clean the dash switch up enough for them to work or if the spade connectors to the dash switch are tight pulling them off and putting back on a good few times might clean them up enough to work, the same for other connectors

better still clean all connectors, make sure they fit tightly, make sure they are fully insulated

with wires make sure they are tight into connector ends and are fully insulated

you can get various stuff to keep the conections clean

alteratively you could check the continuity of each section of wire and the connections

you'd also do yourself a favour by getting a wiring diagram - I'd suggest as it includes wiring diagrams and loads of other useful stuff buting a Driver's Handbook - http://www.mgocshop.co.uk/catalog/Online_Catalogue_Handbooks_5.html

ball is now in your court!
Nigel Atkins

Here is a link to Paul Hunt's excellent bit on wipers http://www.mgb-stuff.org.uk/electricstext2.htm#wipers. I know its about MGBs but most of the components are the same on both cars. Oh, and by the way, if your motor has four wires it is single speed. The 2-speed motor has five wires.
Mike Howlett

Mike,
good link to excellent site

I'm not disagreeing with you or criticising your post and input but so as not to complicate things about one or two speed switches and motors I'll just say as I usually do, never assume the parts and components fitted to the car are original or correct or that they are working fully or correctly

note also W's remarks,
>>The switch has three positions Off , pressed half way, fully pressed if this makes sense.<<
>>A lot of additions have been made to the car over the years so wiring color codes could be a little unusual!<<
Nigel Atkins

Thanks for all the help

I'm sorry I can't give accurate info on the car year. It's a round wheel arch model but when I bought it it had a '67 plate. I asked the garage I bought it from about this and he told me that it had been restored some time ago and and lots of new parts fitted. So I'm guessing it's a '67 with new round wheel arches fitted. The engine number is missing. There is a code on the
passenger side A pillar which I think is '67. I'll check it again.
As regards the wiper motor I read that on older cars the motor is hidden behind the dash but on later cars it's where mine is....confusing I know!!

I'll do some more checking of numbers etc and try to be clearer in future.

W Headon

W,
I think that's enough info to assume its might be a '67 that's been altered so parts, components and wiring could be a mix and match

if you can find a plate with a number that starts GAN (or even possibly HAN) that will give original year but it doesn't matter too much for this now

as Mike's link shows the double speed motors could be fitted to eariler cars with the addition of the extra wire and double switch - as you have four wires connected it will only run at single speed

the brown/light green wires can look just brown when viewed at some angles or you could have a brown(only0 wire replace it

for a quick fix and see try the rapidly turning the switch off and on with the ignition off and taking one wire and spade off the switch at a time and putting it back on to clean up the connection (spade must be fairly tight of course

ETA: wiper motors were all in engine bay passengers side, tucked awkwardly under the wing edge for yours
Nigel Atkins

WH, I just read this thread quickly and noticed you refer to an "inline fuse" being OK.

Do you mean the fuse box fuse, which should be the only one, or an extra fuse someone has fitted "inline" in the feed to the wiper switch?

If the latter, you need to check the fuse box fuse too.
JB Anderson

Nigel, Paul Hunt's site is worth looking at for all sorts of problems. Thanks for pointing out that these cars, probably more than most, get modified, sometimes in good ways, sometimes not. I am as bad as anyone and have fitted 2-speed wipers to my 1966 car. The wiring of the wiper motor and switch is confusing, at least it is to me. This is because once the switch is "OFF" power has to continue to be fed to the motor until the park switch is activated. When that happens a reverse emf is applied to the motor stopping it dead so that the blades don't creep back up the screen as the motor slows down.

The wiper motor on the mark 1 and 2 midget is beside the heater box. On the mark 3 it moved to under the edge of the LH front wing. As far as I know it was never under the dash - that's the MGB you are thinking of.

JB there is a separate wiper fuse in the wiring harness. It is near to the fuse box. My car has a new wiring loom and the in line fuse is present.
Mike Howlett

by the colours of wires in the original post it seems W's car may have the later wiring which has an in-line fuse for the wiper motor and as Guy points out it (should/might) also serves the heater motor (which I forgot)

if the '67 car has been updated perhaps it's updated to RWA spec as it has the round wheel arches

W,
the car is negative earth, has it got a dynamo and control box or alternator?

if you can photos of dash switch, (and dash) the motor connector and wires (and engine bay) may be useful if you can post them

and don't forget Guy' suggestion to clean bothends of the fuse connector that touch the fuse (and even fuse)

ETA: Mike posted whilst I was typing (as usual) - nothing wrong with updating the cars and making them more useable to what you want - I've quite a few mods on mine most don't show but make the car better for regular use
Nigel Atkins

Thanks for all the help. Just to clarify one thing.

When I removed the greeen/white wire from the switch and replaced it with a wire directly from the battery, the switch worked as did the wipers so then my problem has to be before the switch. BTW I checked the inline fuse with a multimeter and it's okay.

Shouldn't I be getting +12V to one of the wires on the switch with the ignition on? I don't have 12 V?

Anyway, I'll do some further investigation and maybe take a few photos.

Thanks again
W Headon

I didn't rule out the switch as I wasn't sure how you connected the battery live to it and from your posts I wasnt sure how much you already know (probably more about car electrics than me)
if youre happy that the switch works then yes it would be before, the fuse might be OK but what about the connectors and wires

from dash switch backwards youve got
. in-line fuse
. ignition switch
. live supply from battery
. all connections and wires on above

a bit of crud can be enough to drop the power getting through which is more noticeable on hungry things like motors, horns, headlights, hazards, ect.

what V you get depends on battery power and condition of all the connectors and things interrupting the wire supply see the thread on here titled Electricery

does your heater motor work? (assuming its off the same in-line fuse)

if it's in the wires Guy has a good pin method to find it
Nigel Atkins

Okay, I've got to really kick myself on this one ... Umph!!!

I never actually looked at the ignition switch ... and guess what...
one little dangling green/white wire!!!

Go on Del say it! What a plonker!

Anyway, all's well that ends well. I've learned a little more.

Thanks for all the help!

See you next time!
W Headon

well done on finding it - and admitting your mistake, we've all done such things some of us a lot more times than we should

the red covered owner's Handbook covers cars from '66 (with a suplement) to '73 so would be of great use to you for lots of other stuff too Ref: 0057 - http://www.mgocshop.co.uk/catalog/Online_Catalogue_Handbooks_5.html
Nigel Atkins

Well done for spotting it!

You keep referring to "pressing the wiper switch" which implies to me that your car has rocker type switches rather than the toggle switches that it should have for a '67 car. Maybe its a "bitsa" car that has been put together with parts from a later car. But with both a later style dash plus round wheel arches I would imagine that it is a 1973 or later car. Its possible that someone has tried to pass this off as an earlier car in order to get the tax exemption.
Guy W

'Its possible that someone has tried to pass this off as an earlier car in order to get the tax exemption."

Spot on I'd say.
W Headon

tut, tut, tut, Guy you're getting as bad as Christian and David, to name two, for not reading previous posts

it's a bitsa and a bit more - or an updated car - or possibly a backdated car

W,
the GAN (or HAN) number, if not changed would give the game away
Nigel Atkins

Not true Nigel. Earlier comments, yours included, were that it appeared to be a 67 car, with later additions like the round wheel arches.

No one had commented, as far as l recall, on the rocker switch style of dashboard. With this significant later car feature, and the round wheel arches which would not be a simple alteration, l was pointing out that it is more likely to be a later car disguised as a 67, rather than the other way around!
Guy W

OK, I call that from now on, W. has to fully disclose all of this information about his car, in his first post, when he asks new questions on the board.


Norm "bossy" Kerr

Norm Kerr

Guy,
no dispute from me on your suggestion only that it might be a backdated car
Nigel Atkins

This thread was discussed between 09/08/2012 and 11/08/2012

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.