electrical wizard required please...!

The purple/black cable is an ignition fed supply, that provides the power for the motor to park. When you turn the switch on, the black wire should get 12V to activate the motor (which is what you're doing by bridging the two wires).

By the sound of it, the fault lies with the swtich. Have you checked the switch is getting/putting out 12v?

Or the black cable to the motors broken

Ah ok at least I understand the basics now...I suspect the black wire isn't getting power; I'll check. And I'll check at the switch side again, too.

Many thanks

well no, that doesn't seem likely as I can get the motor to work by bridging the cables, after all

Ignore the advice, it's all wrong.

Absolutely dead simple. I'll explain how it works.

OK, there are two positive feeds to the motor - a constant which allows the motor to return to the park position and a switched one.

The first goes through the nearside rear tailgate strut (you'll notice a spade connector at either end) and is the constant +12v feed.

The second switched one, and the one at fault, goes through what looks like a boot light switch on the passenger side. THe passenger side plunger has a metal centre and the drivers side plunger is plastic.

If you look at the bottom of the bootlid frame on the passenger side, you'll see a 3/4" metal disc. This creates a contact with the "plunger" on the rear panel at the passenger side when the boot is shut and this is where the +12V from the dashboard switch goes to. If you trake it out, you can see the green wire, the same as at the back of the dashboard switch, hooked up to a spade connector on the bottom. In effect it turns the passenger side plunger into a connector. What happens is that both the top of the plunger and the metal disc in the tailgate frame get covered in crap or get surface rust on them. All you need to do is get some sandpaper and clean them up.

If you need a photo, reply to this and I'll do you one.

The cable from the switch to that point.

Ah I see what you mean; yes that makes sense; thanks

However Conors probably right, the spring contacts are the most likely fail point.

Hi Conor,

I suspect you will have saved me a LOT of time; I'll check this out as soon as I get to the car. Thank you very much.

No problem. Got a D reg Laser and I get the same problem every few months in wet weather. Just done it the other week myself but because the bloke who resprayed my car put the plastic one on the wrong side.