'Lights left on' buzzer mod for Mk1's

Mk1 ‘Lights left on’ buzzer mod for pre-'89 fuseboxes

Someone else posted up a thread about the plug-in relay mod for the late (post '89) fuseboxes. However, after messing about with the relay and wiring for a bit I've got it working on the earlier fuseboxes

I’m not an auto electrician by any means. This is what I did to get the buzzer working on my ‘83 Golf Gti. Feel free to do the same but I can’t / won’t be responsible for any problems you may encounter should they arise

A - Find a donor !
The relay is a Seat part so you’ll need to locate one of the following Seat produced cars in the breakers :

Seat Ibiza 6K (’93-’02) or it’s Cordoba / Vario variants
Seat Inca van (’95-’03)
Caddy 9K van (’96-’05)
Polo Saloon / Estate (not hatch) – similar years to the Caddy van






B – Get the parts
The fusebox can be found above the drivers side footwell on the donor car. You’ll need to take off the drivers side glovebox and remove the cardboard undertray to get at it properly. When you do you’ll see something like this. The relay we want is top left



Carefully remove the relay from it’s plug. If you just pull on it then it’s likely that the relays cover will just come off. Wiggle it and maybe try and get a screwdriver behind to lever it off

Lift the fusebox from it’s mounts by pushing up the clips on the sides, then drop the box down

You can then take off the relay holder from the top of the fusebox. You need to push a screwdriver under it and lever it up while pulling it towards you



When the holder is free spend some time tracking the wires back to the main loom and cut them there. You want as much wire on the plug as you can get as it’ll make things a bit easier later

When done you should have this :




C – Wire into your Mk1
You’ll need to isolate the battery before doing any work. When you’ve done that, remove the passenger side undertray and drop the fusebox down. Happily the Seat relay holder will slide right onto the top of a Mk1 fusebox. Pick your preferred location !



Three of the 4 wires you’re looking for on the Mk1 loom terminate at the red plug on the rear of the fusebox. These are grey/red, grey/black and black/yellow :



You need to connect as follows :

white/red on relay holder to grey/red on the Mk1 loom
white/black on relay holder to grey/black on the Mk1 loom
black/yellow on relay holder to black/yellow on Mk1 loom

How you connect the wires is personal preference although Scotch Lock are fine for this IMO.

The only other wire to connect is the brown/red on the relay holder. This connects to the brown/white door pin earth switch on the Mk1. I extended the wire from the relay holder, passed it through the body of the car and connected directly to the door pin switch (‘piggyback’ spade connector), but upto you where you trace the wire and attach.

Fit relay to holder



Just have to refit everything, reconnect battery and test ! The buzzer will sound when the door opens if the lights are on but the ignition is off. It shouldn’t sound under any other condition.

As said, this got it working on my Mk1. If you try it let me know how you get on.

Cheers !

Good work (Y)!

Sick mod man