marsie

My 1990 sapphires electric windows aren't working so i have done the following(on the drivers door)

1-Stripped switch cleaned all contacts
2-removed motor and checked wiring (all seems ok??)
3-checked motor across battery (ok both directions)

if i connect a voltmeter between the 2 wires i get 12v when operating the switch and if i connect the voltmeter to the wires individually i get 12v down each wire (depending which way the switch operates) but when i connnect the motor- nothing!

I am at a loss?? wiring seems ok, motor seems ok but both together wont work??

Anyone got any ideas??

cheers
Paul

RichieST

iTrader: (2)

Is there a good earth? Sounds like not enough current can pass through the wiring, the motor is trying to pull too much load which is why you are seeing 0 volts with it connected. Try earthing the motor casing to chassis.

RichieST

iTrader: (2)

Buggered relays can also give you the same symptoms!

st220kyle

Check continuity of - and + at the motor itself, if no (-) it's earth related, if no (+) probably be relay

marsie

does the motor also need to be earthed? i assumed the switch sent an earth down one wire and +12v down the other and reversed when the switch was reversed??

in the door both wires get +12v in turn when the switch is pressed and if i put the multimeter across the 2 wires i get 12v both directions which suggest i am getting an earth??

or am i missing something??

st220kyle

One wire will be for 'up' and one wire will be for 'down', you have 12v on both,which would indicate you have no earth, put a temporary wire from the the car body to the motors (-) connection and see what happens

marsie

Hmm, electrics have always been a dark art to me!! I will have another look tomorrow and try your suggestions

Thanks
Paul

Marc sierra

iTrader: (1)

The motors are hardly ever the problem. The switches are crap though. I've replaced all the switches with Mondeo/Scorpio switches for that reason.

marsie

Thanks Marc, seems funny that all 4 are dead. Is swapping to mondeo/scorpio switches fairly straight forward?
Paul

marsie

Now sorted . Took the switches out and all the relays and blasted everything with contact cleaner. Left it all to dry and it works

Thanks for all the advice everyone
Paul

KSA-Cossie

iTrader: (4)

I'd like to know this too

Marc sierra

iTrader: (1)

It's in both my project topics

KSA-Cossie

iTrader: (4)

Cheers Marc, I'll take a look now.

martysmartie

iTrader: (1)

There are no relays!

This is what causes the problems as they are powered directly via the switch, which causes the contacts to become dirty, perhaps other switches are more resilient etc, but none the less it does not solve the underlying problem.

Martin

marsie

No, i found that out. But taking all the relays out and cleaning the terminals got my heated rear window working so was an added bonus. Been using all the windows today and they are getting better all the time. I guess the problem was due to the fact the car had been stood a while?
Paul