lights on problem

Hi  to all again
It is time for the mot again but i have noticed a problem when driving my cab back the other evening for pre warm up, my lights are not bright and to add to that when lights are on my windscreen wipers do not work, which was a hard drive back the other night apart from age catching up on me. Turn the lights off and the windscreen wipers work again.
I guess a relay hopefully?
 

1. Clean your main grounds, that is from the Battery to the frame and from the frame to the engine/tranny.

If there is a .5Vdc drop in voltage between the frame and the battery you have a bad cable.

Briano's Quick Grounds test. | Volkswagen Owners Club Forum

2, Relay your headlights, it is the quickest and cheapest mod that you can do for your car.

H4 Headlight Relay Harness Improve Brightness 12V 40A Double Relays Ceramic Socket Car Relay Harness Kit : Amazon.co.uk: Automotive

It sounds as if you have a bad fuse, and that your wipers are providing the current path for your headlights.

This re-routs the high current load off of your headlight switch and directly feeds the headlights straight off the battery.

Before voltage at the headlights.


After relaying.


3. Possible X or (Load Reduction Relay issue.)

4. Ignition switch issue. as in replace it.

Thanks i will look over the weekend

Relay the headlights helps a lot with the brightness and load on the switch/wiring.
You can buy a kit from eBay etc.