Boxster Top Not Working
05-01-2010, 09:31 AM
#1
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Boxster Top Not Working
I bought a 1997 Boxster a few months ago. Top has never worked, top motor never runs. All four microswitches are working. When I pull the top release the windows drop a few inches. Have tried a second top relay with same results, windows move down but motor never runs. I can put 12 volts on the top motor and it will run. When I pull the emergency brake lever the brake indicator light comes on. Any ideas?
05-04-2010, 06:38 AM
#2
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Wire between the relay and the motor is gone? I can post all the diagrams I have from the technical manuals if that helps. Check if there is flow between the motor power and wherever that wires goes (to the relay I assume).
05-04-2010, 09:15 AM
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roof
The motor is activated if:
.no speedometer signals greater than 5 km/h (3 mph) are
present
.the "convertible top unlocked" signal is connected to ground
.electric motor plug connection is plugged in
.the "convertible top unlocked" signal is connected to ground
.fuse 86 (row: 8, number: 6) is in order
.terminal 15 is connected via ignition lock
.the parking brake input is connected to ground (parking brake
engaged)
.no speedometer signals greater than 5 km/h (3 mph) are
present
.the "convertible top unlocked" signal is connected to ground
.electric motor plug connection is plugged in
.the "convertible top unlocked" signal is connected to ground
.fuse 86 (row: 8, number: 6) is in order
.terminal 15 is connected via ignition lock
.the parking brake input is connected to ground (parking brake
engaged)
05-04-2010, 07:04 PM
#5
Drifting
Have you checked the relay? Anything mechanical is prone to failure.
FYI, you can disable the parking brake and speedometer inputs via simple mods to the relay, and eliminate those as possibilities. (As a side benefit, you will be able to work the top while rolling at low speeds, too.)
FYI, you can disable the parking brake and speedometer inputs via simple mods to the relay, and eliminate those as possibilities. (As a side benefit, you will be able to work the top while rolling at low speeds, too.)
05-04-2010, 07:10 PM
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Have you checked the relay? Anything mechanical is prone to failure.
FYI, you can disable the parking brake and speedometer inputs via simple mods to the relay, and eliminate those as possibilities. (As a side benefit, you will be able to work the top while rolling at low speeds, too.)
FYI, you can disable the parking brake and speedometer inputs via simple mods to the relay, and eliminate those as possibilities. (As a side benefit, you will be able to work the top while rolling at low speeds, too.)
05-04-2010, 07:18 PM
#7
Drifting
I posted a thread over on RennTech. Copied here:
http://www.renntech.org/forums/index...ven-when-movin
The fascia rail was an unreliable ground for the handbrake pin and lead to intermittent failures on hot days, where I had to reach down and jiggle the wire to get the top to move; I eventually moved the ground to a spare stud deeper up under the dash and haven't had an issue since.
As a general rule, I never operate the top when moving faster than 20mph (I think new Boxsters allow up to 30mph from the factory?), but if you do this, there's no idiot-interlock to prevent you from actuating it while doing 165 down the autobahn. You just have to be smart enough to, you know, not do that.
http://www.renntech.org/forums/index...ven-when-movin
Originally Posted by me
I was never quite sure if it was a 'feature' or a 'defect' (I'm thinking defect), but having to stop the car and pull the handbrake to operate the top sure is annoying. At the PCA fun run today, another Boxster owner told me how easy it was to bypass the handbrake and speedo signals, and I set upon it immediately when I got home. Took a couple tries, as the bolt I tried to ground the relay's handbrake pin to apparently is grounded to nothing but plastic, but I finally find a spot to ground it, and got it working. So I can finally operate the top while rolling 
I did a search on here and didn't see the procedure. If anyone's interested:
1. Pull the cab top relay (under the dash, above the fuse panel- it's a double-wide relay, was the only double relay on my panel. Mine had all the pin functions labeled in German on it.)
2. Bend pin 18 (speedometer) over. I covered in with electrical tape, but it's probably not necessary.
3. Bend pin 15 (handbrake) over.
4. Attach a wire to pin 15 and ground it to something on the car- I dremeled the paint off the fascia rail under one of the screws of the lavender OBD port, and grounded to there.
5. Reinstall the relay.
It's completely reversible if you screw something up. Just try not to break your relay. I did discover if it's not bonded well, the top will NOT operate. So, there is potential here that if the connection loosens, the top might not operate.
I did a search on here and didn't see the procedure. If anyone's interested:
1. Pull the cab top relay (under the dash, above the fuse panel- it's a double-wide relay, was the only double relay on my panel. Mine had all the pin functions labeled in German on it.)
2. Bend pin 18 (speedometer) over. I covered in with electrical tape, but it's probably not necessary.
3. Bend pin 15 (handbrake) over.
4. Attach a wire to pin 15 and ground it to something on the car- I dremeled the paint off the fascia rail under one of the screws of the lavender OBD port, and grounded to there.
5. Reinstall the relay.
It's completely reversible if you screw something up. Just try not to break your relay. I did discover if it's not bonded well, the top will NOT operate. So, there is potential here that if the connection loosens, the top might not operate.
As a general rule, I never operate the top when moving faster than 20mph (I think new Boxsters allow up to 30mph from the factory?), but if you do this, there's no idiot-interlock to prevent you from actuating it while doing 165 down the autobahn. You just have to be smart enough to, you know, not do that.
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05-04-2010, 10:20 PM
#8
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Have you checked the relay? Anything mechanical is prone to failure.
FYI, you can disable the parking brake and speedometer inputs via simple mods to the relay, and eliminate those as possibilities. (As a side benefit, you will be able to work the top while rolling at low speeds, too.)
FYI, you can disable the parking brake and speedometer inputs via simple mods to the relay, and eliminate those as possibilities. (As a side benefit, you will be able to work the top while rolling at low speeds, too.)
