The bank of relays is just above the fuse panel down in the left side foot well. Does anyone know the trick to pulling it down and out so you can check the relays?
Convertible top on my 05' Boxster S is up/closed but soon as I try opening it, the main 30A fuse blows instantly for some reason. I need to do more electrical debugging but need access to the pair of relays located on that support.
Accessing Relay Support 1 on 987 Boxster / Cayman
So, I got the relay support out, you just have to manhandle it a bit. It helps a lot to unbolt the main fuse panel from the sidewall first allowing the wire bundles some room to move out of the way. A single 10mm nut and it comes off. You also have to disconnect the wires from the brake and clutch switches as well. It goes back in the same way it came out. It helps to pay close attention to which tabs go where in the mounting bracket up under the dash.
- Boxster fuse and relay panels.jpg (1.11 MiB) Viewed 4837 times
-mark
near Seattle, WA
85' NA 944 race car / 86' 944 Turbo
23' 718 Cayman GT4 RS
17' Macan GTS
near Seattle, WA
85' NA 944 race car / 86' 944 Turbo
23' 718 Cayman GT4 RS
17' Macan GTS
-
Tom
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Any progress on the fuse blowing? Burned out motor maybe? Which fuse it is? I have the e-schematics somewhere and may be able to look up its circuit...
Tom,
I found this circuit diagram, but it doesn't show the top up/down control switch by the handbrake or the microswitch up near the latching hook at the top of the windshield. I'm assuming both of those interface with the rear control module somehow but it would be nice to confirm that.
Fuse E3 is the one that blows. It's a Maxi APX style fuse so not easily sourced at your local auto parts store...
Both relays checked out as good on my bench. With the relays out, you have access to the motor wires directly at the relay socket pins. I was able to use a separate battery & some jumper wires (also fused with a 30A fuse) to power the motor directly. I made the clamshell open a few inches then swapped the wires around and closed it, almost.
Put the relays back in, turned the key and the dash display said the top was not closed. Using the center console button, I was able to make the clamshell go down the rest of the way and stop. Soon as I tried to open it again, the fuse blew.
Something isn't quite making sense, but I haven't figured it out yet. I have a Durametric but some of the status messages are a little confusing. I need to look at actual values I guess and try to get a better understanding of what's going on.
I found this circuit diagram, but it doesn't show the top up/down control switch by the handbrake or the microswitch up near the latching hook at the top of the windshield. I'm assuming both of those interface with the rear control module somehow but it would be nice to confirm that.
Fuse E3 is the one that blows. It's a Maxi APX style fuse so not easily sourced at your local auto parts store...
Both relays checked out as good on my bench. With the relays out, you have access to the motor wires directly at the relay socket pins. I was able to use a separate battery & some jumper wires (also fused with a 30A fuse) to power the motor directly. I made the clamshell open a few inches then swapped the wires around and closed it, almost.
Put the relays back in, turned the key and the dash display said the top was not closed. Using the center console button, I was able to make the clamshell go down the rest of the way and stop. Soon as I tried to open it again, the fuse blew.
Something isn't quite making sense, but I haven't figured it out yet. I have a Durametric but some of the status messages are a little confusing. I need to look at actual values I guess and try to get a better understanding of what's going on.
- Add Pictures/Files
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- ckt diagram.jpeg (86.76 KiB) Viewed 4829 times
-mark
near Seattle, WA
85' NA 944 race car / 86' 944 Turbo
23' 718 Cayman GT4 RS
17' Macan GTS
near Seattle, WA
85' NA 944 race car / 86' 944 Turbo
23' 718 Cayman GT4 RS
17' Macan GTS
Finally got around to fixing this blown fuse problem.
Last August, I had a shop install new springs and shocks. At the left rear upper shock tower, a wire bundle got trapped under one of the flange nuts for the strut mount. The black and green top motor wire pair were in that bundle and the black wire got the worst of it with its insulation being destroyed, shorting the wire to chassis GND there.
With the black wire shorted to chassis GND the "close the top" circuit works normally. That's why the shop told me they had no trouble with the top. They installed the springs/shock, shorted the wire, closed the top. Done...
When you "open the top", the black wire needs to be +12V and the green wire GND. Direct short. Blown fuse.
It's always something...
Last August, I had a shop install new springs and shocks. At the left rear upper shock tower, a wire bundle got trapped under one of the flange nuts for the strut mount. The black and green top motor wire pair were in that bundle and the black wire got the worst of it with its insulation being destroyed, shorting the wire to chassis GND there.
With the black wire shorted to chassis GND the "close the top" circuit works normally. That's why the shop told me they had no trouble with the top. They installed the springs/shock, shorted the wire, closed the top. Done...
When you "open the top", the black wire needs to be +12V and the green wire GND. Direct short. Blown fuse.
It's always something...
-mark
near Seattle, WA
85' NA 944 race car / 86' 944 Turbo
23' 718 Cayman GT4 RS
17' Macan GTS
near Seattle, WA
85' NA 944 race car / 86' 944 Turbo
23' 718 Cayman GT4 RS
17' Macan GTS
-
Tom
- Site Admin
- Posts: 8913
- Joined: Fri Jun 25, 2021 2:04 pm
- Location: Silicon Valley, CA
- Has thanked: 931 times
- Been thanked: 3988 times
- Contact:
Great find, and very much appreciate the follow up. I once did that by trapping a wire between the block and bell housing on a different car. It was in an inaccessible spot you could not see, so took me forever to figure out. It's always something indeed!markl951 wrote: Sun Nov 20, 2022 9:18 am Finally got around to fixing this blown fuse problem.
Last August, I had a shop install new springs and shocks. At the left rear upper shock tower, a wire bundle got trapped under one of the flange nuts for the strut mount. The black and green top motor wire pair were in that bundle and the black wire got the worst of it with its insulation being destroyed, shorting the wire to chassis GND there.
With the black wire shorted to chassis GND the "close the top" circuit works normally. That's why the shop told me they had no trouble with the top. They installed the springs/shock, shorted the wire, closed the top. Done...
When you "open the top", the black wire needs to be +12V and the green wire GND. Direct short. Blown fuse.
It's always something...
-
boxstermike06
- Posts: 17
- Joined: Sat Aug 19, 2023 6:17 am
- Has thanked: 1 time
- Been thanked: 2 times
2.7 987 , 06 It's possible your problem is in the covert top transmission. There are two of them and there's one plastic gear that disintegrates, jamming the mechanism. That might cause your issue. It's a 100 bucks for two new gears but it's a DIY job. Realignment is a pain but if you watch the online videos you'll get the hang of it.