Re: Trying to diagnose a why the convertible top won’t operate.

Details: ‘99 Boxster 5-speed with 130k miles. I put the top down last weekend and after a day of driving, I could not get the top to close. I lifted and released the hand brake (hard) numerous times and used my finger to trigger the latch & unlatch sensor, but no luck. I eventually popped the push rod ball sockets off so I could do the “emergency top close”.

The parking brake sensor appears to work, when lifting and releasing, the PARK dash goes on and off. I have had issues in the past and cleaning with compressed air resolved the inability to light the dash light and operate the top.

I removed the top latch sensor and both the latched and unlatched sensor mechanisms make audible clicks. I re-soldered the 8 currently soldered points and cleaned it with compressed air.
I replaced the switch and the windows drop the two inches when unlatched and the windows roll all the way up when latched, but nothing from the top motor when hitting the convertible switch with the latch open and the hand brake up. Can the switch send the proper signal to the window regulator, but fail to indicate the proper status to the top motor?

I have also checked and replaced the fuse (D-3).

Is it likely the convertible top rocker switch is bad? Any other diagnostics to initiate before coughing up the dough to replace sensors & switches would be appreciated.

The latch's microswitch is actually two switches in one.
If you only feel/hear one click when pushing on the pad (where the latch closes) then the switch is not making the second contact.
The first click (contact) is for the windows to drop. The second click is for the motor's signal.
You can pull out the latch mechanism and look at it from behind to see if you are getting the two individual contacts.
If not, replace the switch. it's not too expensive and easy to replace.
Good luck.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

Thanks Pedro, both mecahnical swithes in the latch make an audible click, but I'll order a new one and see if that resolves the problem. I found one (986-613-795-02) for $67 with free shipping.

Put a continuity tester (e.g. multimeter on Ohms) on the output of the switches and verify their function.

Where would I check continuity on the latch sensor? The three pins at the connector? I have a multi-meter, but I'm no E.E.

Thanks in advance.

Bob

Diagnostic instructions: [www.justanswer.com]

On Mike Focke's page there is a clear picture of the relay pin numbers: [sites.google.com]

Here is the wiring diagram (on which I have highlighted the relevant portion), which also indicates the wire colors (brown/green and brown/black for relay pins 19 and 14, respectively). Since you're testing with the relay in it's easier to go by wire color:





Edited 1 time(s). Last edit at 06/02/2014 11:08PM by Boxsterra. (view changes)

I'll take a look tonight, thanks!

Handbrake switch must be off/up (which causes the "Brake" light).
Two microswitches in the center of the windshield frame must be off (not pressed).
No signal from the speed sensor.
Relay must be functional.
Fuses B6 and D3 for the Boxster (or C3, B5, D3 for the 911) must have continuity.

I'm guessing fuse B6 ( "Convertible Top Boxster" ) is blown.



Edited 1 time(s). Last edit at 06/02/2014 12:06PM by Boxsterra. (view changes)

Thanks Boxsterra, I didn't catch the B6 on the fuse diagram, but it is not blown, replaced it anyway with no luck. The handbrake seems to be working fine. I bent pin 18 on the relay years ago, I supose the relay could be bad. I'll start with the latch sensor and see what happens.

Holding the close button on the top while repeatedly toggling the microswitch with your other hand will cause at least some movement and identify that as the culprit.

With the key on, handbrake up (dash light on), latch open, top down dash button held, poking my finger in the hook opening repeatedly, NO top motor activity. I'll pull the switch again tonight and check the continuity.

Thanks, Boxsterra. I was able to confirm the switch was bad, I ordered a new one and now the top is back in action!

I had the car in for another service. I told him about the problem. The tech. cleaned the switch contacts (Which he said was a common problem). I have not had a problem since.