There's a ground wire coming from the switch? Didn't think there was.

Yes. Most of the switches in the car are negative, not positive. Note the brown wire in the schematic: it is labeled GP4 (ground point 4).

When you activate the stock switch to either open or close the top, you are sending ground through the open or close wires (Black with blue stripe and black with green stripe) to the controller.

Right. Where would I get a 12v feed from? I'm guessing the original loom going to the switch has one?

The only 12V+ going to the switch is for the illumination LEDs and will only be active when the headlight switch is in an on position. Everything else is ground. You'll want to get power elsewhere (cig lighter, phone harness, etc.).

Oh, Christ. Didn't realise that the switch would work with just a negative and ground. That's what's thrown me.

You'll have to excuse me mate, very new to this.

Charles, brilliant Charles. Can you at least add a little touch and make it a tad more exotic??? Something like.... this whole system hooked up to a IR remote keychain. Something I can grab out from my pocket, click-it, and the windows lowers and the roof starts to open while I'm walking to my car (given you've unlatched it before the staged show loll).

No? Anything less-deja-vu that you could quickly rig for us bored cabintrophobic members?

Only problem with that is that you'd have to have the key in the ignition for the 12v feed to be live.

On the other hand, do they have to be timed relays? If they weren't, it would be the same as holding down the button even after the roof is stopped. Is there anything wrong with doing that? Would save a lot of hassle in getting a timed relay wired up to the right time, and you could put a simple make or break relay in there.

I bet you could design small form factor Central Power Management system as cost effective as the one you are doing now (one more 12v relay!). Add IR range sensors at both ends so this CPM does it's thing automatically when you walk towards your car ;)

My roof is manual, can you believe that mate. Takes 3~5sec to bring down & up and ALWAYS works. No more bending-twisting-snapping evil sounds ever for me thank you very much. Had bad experiences with the 986 roof here :/

Not to negate all your work and ideas, but there is an easier way. Shehadehd has made one for $200 that is simple plug and play and it has the service mode option built in and it operates on the go until about 20 MPH.

http://986forum.com/forums/general-discussions/51527-all-new-comfort-top-6.html

He says that currently he can only ship limited numbers, so if you want one, get hold of him.

Tony

$200?!?! :eek:
That's ridiculously overpriced. You'd be better off buying one from Tom for $79...even better off taking 30min to make your own for $20.

I have tons of respect for him, but $200 for a home brew hack is nuts...

$200 is obsurd. Who would pay that when you could buy an arduino and the components for about a tenth of that. I'm doing it this way as it's a learning curve for me too :)

Anyway, would what I said matter? Having a simple make or break relay that would simulate pressing the button, but not releasing. It'll be like holding the button down constantly. Would that be an issue?

It should work since the top is locked out once fully opened or closed, but I don't like it.

I've been reading this thread with interest trying to figure out why it will NOT work and I can't see any reason that it should not work as intended.

When the top raises and lowers you are supposed to press the button until the dash light for the roof goes off, but if you hold it longer there is no issue as you can hear that the roof motors have depowered and shut down in any case.

Of course this solution does not have the convenience of the auto Maintenance position but using the key to stop the roof seems fine.

The only worry is that if the car can be in motion with this mod and for some reason you need to stop the roof, the only way is to use the ignition key...not good:eek:.

So as long as the parking brake must be engaged your mod has no issues in my opinion.

Nice work coming up with this idea.

I already have the arduinos so I'll build the more advanced roof DIY switch.

Well as a matter of fact you CAN get one of these relays with a remote!

DC 12V Relay Wireless Remote Control RF Switch on Off Switch Delay Time Timer | eBay

Wow, what a find. Although looking more like a bomb making device to me. TerroristParadiseTooling.com lollll.

Seller writes: "if you want to get more delay time, just change to a bigger capacitor".

Funny but not all that funny when you think about it :/

To fix that, you wire up a third relay that makes or breaks the power that feeds both original relays, so if you press this button, the roof will stop. You can then name it 'emergency roof stop'.

I'll probably order a timed relay and try it just for the hell of it as, if it works, you can wire up said relay for 3 seconds which would make the roof open enough to service the engine :)

Just realised something...

As well as doing this for the spoiler switch when I reroute it to a 996 dash switch, I can also wire in a relay for the indicators. You know a lot of modern cars have a feature where touching the indicators automatically puts them on for three flashes? Easily done with a relay. Might be a nice feature! Will have to find the indicator wires.

Forget that - just realised that even if you click the indicator stalk down, it'll still turn off after three flashes :(