Alex
Nordschleife
- Joined
- 6 Mar 2014
- Messages
- 22,185
It's Friday, it's Sunny, Steve Wright's Serious Jockin' is on the Radio. There's only one thing for it - Serious Moddin'!
Ever since I've owned my 996 I've wanted to be able to lower/raise the roof in motion at low speed, something similar to what the Smartop ECU does, allowing the roof to be operated up to 28mph. I know I could just buy the smartop ECU but begrudge paying £300:
https://smarttop.uk/product/smarttop-for-porsche-911-convertible-996/
I knew there could probably be a way on modifying the speed input wire going in the ECU, so yesterday did some routing around on the internet. Turns out if you own a 986 Boxster it's a 5 minute job to do it and also free. Simply a case of removing the convertible top relay from the footwell and bending pin 18 to disable the speed input. Handbrake override can also be done, but personally I'd sooner just put the brake on one click and then use the roof, simply as a safety feature so no idiiot can press the top down button on the motorway and rip the bladdy roof off.
Boxster hack:
But it turns out the 996 doesn't have said relay as the ECU does all the control of various microswitches and motors. After more digging about and having a good gander of the 996 wiring diagram (copy of it on here):
Sheet 7 - http://www.911uk.com/docs/911_996_workshopmanual_wiring_1999_2000.pdf
They grey / pink wire going in top the top ECU is the speed sensor wire. Apparantly all you have to do is snip this wire and bingo - the roof can be operated at speed:
https://www.renntech.org/topic/38-how-to-raise-the-cab-top-while-moving/
I'm going to attempt it over the next few days and will report back my findings once done. I know I could go down the route and fit some sort of resistor in there to up the limit to 28mph from the current 4mph but seeing as it's only me that uses the car and I'm not stupid enough to try and use the roof above that speed I'll just snip the wire for now.
Ever since I've owned my 996 I've wanted to be able to lower/raise the roof in motion at low speed, something similar to what the Smartop ECU does, allowing the roof to be operated up to 28mph. I know I could just buy the smartop ECU but begrudge paying £300:
https://smarttop.uk/product/smarttop-for-porsche-911-convertible-996/
I knew there could probably be a way on modifying the speed input wire going in the ECU, so yesterday did some routing around on the internet. Turns out if you own a 986 Boxster it's a 5 minute job to do it and also free. Simply a case of removing the convertible top relay from the footwell and bending pin 18 to disable the speed input. Handbrake override can also be done, but personally I'd sooner just put the brake on one click and then use the roof, simply as a safety feature so no idiiot can press the top down button on the motorway and rip the bladdy roof off.
Boxster hack:
But it turns out the 996 doesn't have said relay as the ECU does all the control of various microswitches and motors. After more digging about and having a good gander of the 996 wiring diagram (copy of it on here):
Sheet 7 - http://www.911uk.com/docs/911_996_workshopmanual_wiring_1999_2000.pdf
They grey / pink wire going in top the top ECU is the speed sensor wire. Apparantly all you have to do is snip this wire and bingo - the roof can be operated at speed:
https://www.renntech.org/topic/38-how-to-raise-the-cab-top-while-moving/
I'm going to attempt it over the next few days and will report back my findings once done. I know I could go down the route and fit some sort of resistor in there to up the limit to 28mph from the current 4mph but seeing as it's only me that uses the car and I'm not stupid enough to try and use the roof above that speed I'll just snip the wire for now.
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