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?