So, I'm through three switches now so I can definitely rule out the switch from being faulty. Shortening the circuit by bridging the pins from the harness instead of using the switch doesn't open the upper tailgate either.

So it’s the harness, apparently. But I have an idea:

The switch never quite worked since I’ve bought the car. However, I was able to open the upper tailgate with the 3rd button on the key. Unfortunately, it has lost it’s programming because of an idiot who was pushing the main tailgate release while I was trying to open the glass part only.

This means the actual lock gets the power and the harness is not THAT damaged as to render the tailgate glass fully inoperable. It’s (most probably) just the switch line.

This harness ends up somewhere. This means, that if I could short the pair of cables that go from the release switch to some junction box at the other end of the harness, where it plugs into something, I can skip the whole damaged part of the harness and open the tailgate glass. Which means also – I can program my keys back.

So the question is: where does the harness from the tailgate release run to? What two cables (or pins on a plug) need to be shortened in order to trigger the opening of the tailgate glass?

Your help is appreciated! Regards etc.,

Wojtek

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WAS: 2006 RRS Supercharged
IS: 2010 RRS TDV8 HSE