Poor Electrics

[martinformorris]

Hi I hope some one can help me, I have non working wipers and heat motor. There are three wires on the wiper motor, and on the wiper switch there are also three wires one of which seems to go to the heat motor switch. There does seem to be power at the wiper motor and switch but it they both are still not working I have clean all the earthing points I can find. Would it be an easy job just to rewire both units i/e running a power lead and an earth ver a switch. Hope some one can help ass this are the only things hold up taking the car for an MOT.

[Alec]

Hello Martin,

is the fuel gauge working as that, the heater motor and winscreen wipers are on the same feed.
If so look at the wiper motor which should have a green wire, black wire and a black\green wire.
The motor is live with the ignition switch on and shorting the black\green wire to earth should make the motor run, if not and there is power at the green wire you'll need to check the motor brushes.
If you have a meter or a bulb and some wires check for power at the green wire and the black\green.
My first guess would be a poor connection at the fuse however?

Alec

[martinformorris]

Thank you I will have a look at that tomorrow, the fuel gauge is working ok.

[bmcecosse]

Not the fuse then........ Has the wiper motor ever worked in your time with the car? If the connections are clean and power present- remove the top plate and un-hitch the drive to the rack - does the motor run now ? If not - suspect the brushes and/or burned out motor.......

[beero]

Early car, check the green wires are terminated okay on the back of the fuel gauge, later model check same on the voltage stabiliser. Is your oil pressure lamp coming on?

[Alec]

Hello BMCE,

"Not the fuse then"

well it still could be, if there is a poor connection, the tell tale is if the fuel gauge goes to E when trying the wipers.

Alec

[bmcecosse]

Well - of course......... But technically - that wouldn't be 'the fuse' - it would be a bad connection AT the fuse .....

[Alec]

Hello BMCE,

absolutely, which is why I said "a poor connection at the fuse however?"

Alec

[bmcecosse]

Yes - but you pulled me up for saying 'Not the fuse then'........

[Alec]

Hello BMCE,

electrical problems can be confusing unless there is some understanding of the principles. In other words, in this instance, a low current device may work with a poor connection but adding load may cause a greater voltage drop so the higher current device will not work.
I'm sure you' ll agree that diagnoses are, at best an informed guess, given the query and many options may be available?
I do try and keep an open mind and give suggestions based on practical experience. It's all about helping others who would not be asking the question if they knew the way to solve it?

Alec

[bmcecosse]

Alec - I'm just yanking your chain on this.........

[martinformorris]

I just want to say thank you for all the help given on here. I am not sure just what was wrong back having tried what people on here have said they are now both working.
Once again thank you for your help.

[Alec]

Hello Martin,

glad to hear that it is working, and that you will have gained with teh experience.

BMCE :- "Alec - I'm just yanking your chain on this.."

Ding ding.

Alec