onetouchtopcontrol

One Touch Top Control

One of the irritants to owning a Boxster is having to be completely stopped while the top raises/lowers. And having to hold the top up/down switch while it raises/lowers.

smartTOP is a $299 relay (with microprocessor and some custom code) that cures both these ills. It replaces the relay pictured below and allows you to press the top up/down switch for a second and release and the top raises or lowers completely. But we can get half way there with a simple no-cost hack.

This hack will allow you to raise/lower the top while the car is moving slowly. It removes the speed sensing capability. Which means it could get dangerous if someone holds that button at 70MPH ! The top structure costs over $3k new.

Cautions include don't rise/lower the top when the temp is below 40F if you have a plastic window (or do it very very slowly in stages lest the window crack), don't raise/lower the top doing more than 20MPH. And, if you have the plastic window and your top's plastic window doesn't lower with a perfectly horizontal fold, get out and do the chop with the side of your hand helping it fold in a uniform manner. Also, if you are going to have the top down for a long time (say during the winter when you use your hardtop) and you have the plastic window, put some soft cloth (or the felt the car came with) as a separator in the fold so the plastic doesn't rub against itself and abrade. I recommend Novus 1, 2 and 3 as a product to use maintaining your plastic window's clarity and flexibility.

Now to the Hack. Credit for this writeup should go to Tom M.

Locate the Top Relay it's the largest relay in the relay cubby to the left of the steering wheel. It's against the front firewall. Once you crawl down there it becomes pretty obvious. Just follow the steering wheel down to the brake/clutch pedals. Then look to the left. You should see the panel with all of the relays there.

Remove the Top Relay (it is the big one).

Locate Pin #18 (it is actually marked next to the pin, look at the third column of pins from the left, bottom small pin and notice the 18 to the right of the pin)

Bend Pin #18 over into the open area on the relay to the right in the picture (or cut it off if you don't ever care about reversing this process)

Re-install the Relay

Result of the "Rolling Top Hack" -- you can now drop your top while the car is rolling as long as you pull up on the emergency brake handle (one click is all it takes to actuate the switch in there) until the light comes on.

You can eliminate entirely the need for use of the handbrake by grounding pin 15. You want to ground pin 15, but not the wire that connects to it through the back of the relay panel.

This is done by either by bending the pin (and connecting a ground to the bent pin) or by pulling the handbrake wire from the back of the relay panel and putting a grounded wire in its place.

Unfortunately, there is no simple hack to give you the "just push the switch for a second" control of the top. Look for used smartTOP relays on auction sites from people who sell (or wrecked) their cars.

Caution: Use at your own risk. Do not drive too fast while operating the top. Do not raise or lower the top in an unsafe manner.

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