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Old 05-19-2008, 04:17 PM
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Woodenewe
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Default Clutch Switch

My 1999 996 C4 6 speed will only start after pushing the clutch pedal hard down to the floor. Yesterday it would not despite pushing and wiggling the pedal. After wiggling the plunger on the switch mounted above and in front of the pedal arm, it did start. Likely I need a new switch, but was wondering why the pedal has to go to the floor. The pedal does not have to go down very far to clear switch's plunger. Is there another switch involved, and if so where?
Old 05-19-2008, 04:46 PM
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Doug Donsbach
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The plunger switch is to detect the slightest pedal depression to allow disengagement of the cruise control. Adjacent to the plunger switch is a bracket holding a micro switch. That switch is gray in color and has two wires attached (brown and yellow). It has a metal blade on its top that is depressed by a tab on the pedal arm when the pedal is pushed to the floor (to satisfy the liability issues associated with people starting cars in gear).

The micro switch is #16:
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Last edited by Doug Donsbach; 05-19-2008 at 05:17 PM.
Old 05-19-2008, 05:04 PM
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Barn996
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That's why this site is so valuable, to get an answer from another member, who helps correct a problem or issue with our 996 911s. Nice not to always have to run to the dealer or indy to solve the problem.
Old 05-19-2008, 05:32 PM
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Woodenewe
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Doug, my thanks for the information. I should have looked harder, but it is a bit difficult for me (6'2", 250#) to get under the dash to look. I'll try again, now that I know where to the switch is.
Old 05-19-2008, 06:10 PM
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Woodenewe
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Yes Doug, it is there, however I wonder if the actuating bracket needs adjustment? Miscroswitches are usually very reliable, and I can't see how the switch is activated. I have a copy of the 1999-996 British manual in PDF, but have been unable to find the exploded view. Can you tell me where the one above came from and maybe from there I can find the installation drawing.
Thank you again,
Bob
Old 05-19-2008, 06:29 PM
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Woodenewe
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I found what I needed on page 30 05 19 (I think that is the page number) and adjustment is described as: "1 to max 2 mm before the limit stop is reached..." . It looks like the pedal arm over its pivot point actuates the switch.
Old 05-19-2008, 06:39 PM
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Doug Donsbach
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The pic I used was from the parts manual. Here is the adjustment spec for the interlock switch, which as you can see is tripped by the extension of the upper part of the arm. The switch should be easy to check - just put an ohm meter on the terminals and reach above the switch and trip the lever. You can do that kneeling next to the driver's door. But I'd expect a wiring problem (the connection to the switch is somewhat exposed), a bent bracket, or something on the floorboard preventing full pedal travel to be the cause of the problem because those switches are usually very reliable.
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Old 05-19-2008, 08:22 PM
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Tippy
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Originally Posted by Woodenewe
Miscroswitches are usually very reliable
Nothing German made that is electrical is reliable...... I replaced my brake light switch at ~80k miles on my old 996. Granted it was only $12, but it failed the day I went to get it inspected.



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