GQ windscreen wiper problems

[Matty852]

Hey guys, I have a 88 GQ I am trying to get back in the road but I can't seem to get the front windscreen wipers to work. I checked the fuse and that is ok and ran through the wiring and couldn't find a fault then went as far as pulling the motor apart and then trying another motor and that still didn't work

Then I had a brilliant spark and realised I should've checked the relay before I went and pulled everything apart I can't find any info on what relay is for the front windscreen wipers, does anyone know which one it is???

[mudnut]

The intermittent wiper amplifier is under the black cover in the engine bay, next to the battery. The unit is anchored to the wall and has a black, orange, purple, light green, brown/ white and brown wires to it. (Connector 144M)

[Matty852]

Cheers mate, I will check it out once I'm back on my feet

[Yendor]

The amp won't stop the wiper motor from working.

With the ignition on, check that you have power in the Light Green wire at the wiper motor.

The wiper switch switches earth. To check the operation of the switch disconnect the connector at the wiper motor. Connect the end of your test light onto the POSITIVE battery post.

The test light should light up when you touch the Light Green with a Black trace with the wiper switch on low speed. On high speed it should light up on the Light Green with a Red trace.

Have you checked that the wiper arm linkages aren't seized?

[Matty852]

All the linkages are fine, I have gone as far as pulling out the old ones and replacing them with a new set, the plastic joint connecting it to the wiper motor arm was stuffed.

[mudnut]

The amp won't stop the wiper motor from working.

Well there you go. I learn something new every day on in this place. Onya Yendor.

[Yendor]

All the linkages are fine, I have gone as far as pulling out the old ones and replacing them with a new set, the plastic joint connecting it to the wiper motor arm was stuffed.

No worries mate, have you check the wiring as detailed above?

[Yendor]

Well there you go. I learn something new every day on in this place. Onya Yendor.

Yeah the amp controls the intermittent wipers and the auto wiper sweep when the washers are used.

If faulty it can cause the wipers to keep going all the time.

[Matty852]

I checked the wires and it seems to be earthing out fine on the low and high settings

[Yendor]

If you have power in the Light Green wire and earth is switch via the Light Green/Black and Light Green/Red when low and high speed are selected, you must have a faulty wiper motor.

Try connecting you test light across the Light Green and Light Green/Black wires. Does the test light light up when on low speed?

Also try bench testing your wiper motor by connecting positive and negative to the corresponding terminals in the wiper motor plug. Does the wiper motor work?

[Matty852]

Hooked up the motor to some spare wires I pulled out earlier and that all works, just checked the light green wire and nothing is coming through so I guess it's time to start finding out where it's earthing out

[Yendor]

Recheck the fuse. Make sure the fuse has power on both sides. Remove the fuse and inspect the terminals inside the fusebox, it's common for them to crack.

Also check the wiring on the back of the fusebox, make sure it not burnt.

If all that is ok and you still don't have power in the Light Green wire at the wiper motor, you will need to check for a break in the wire between the fusebox and wiper motor.

[Matty852]

I have finally got them working it turned out to be a wire shorting out behind the fuse block, thanks heaps for the help the help Yendor, I would've been screwed otherwise.

[mojo53]

I think this thread is about right for my similar problem only the wipers work fine but i don't get any water out of the washer bottle (and yes it has water in it) but i don't know which wires to check for the washer motor to see if it is stuffed....any idea's anyone
Thanks

[mojo53]

Thanks for the wiring diagram Yendor looking at that the light green wire also feed the washer pump, hope it's the same for the 2006 Y61 4.2 Diesel (i guess i will find out as soon as i go check it) :cheers:

[mojo53]

Well i guessed wrong, after removing the Battery and Washer Bottle i found two windscreen washer pumps on my 2006 Y61 4.2 intercooled Turbo Diesel one for the front which does not work and one for the back which does work and the wiring is Blue and Blue/Yellow to one pump and the other is Pink and Red/White, so does anyone have a wiring diagram to suite that one please.
Thanks

[Yendor]

Here's the wiring diagram for the GU.

The Blue wire should have power when the ignition is turned on. The Blue with the Yellow stripe wire should have an earth when the front washer is switched on.

You more then likely have a faulty pump or something is blocking the pump. If you disconnected the electrical plug from the washer pump and connect either a test light or voltmeter across the Blue and Blue/Yellow wire it should light up or show a reading when you operate the front washers. This will confirm that the vehicle's wiring is ok and the pump is the problem.

Cheers Rodney

[mojo53]

Thank you very much for the wiring diagram mate just what i needed

[mojo53]

You were right Yendor the pump was the problem not the wiring, i gave it a couple of taps on the bull bar and hey presto it worked (for time being anyway) thanks for your help at least i know what to do next time it plays up.