Resident Sicko

Got it. Thanks so very much. Will update with good news as soon as I have the okay to start sounding the horn. (Apparently, sleeping kids do not appreciate dad honkin off in the garage late at night)

Resident Sicko

The saga continues...

You may not believe this, but it appears my particular car was assembled by color blind workers. Either that or I have totally buggered things up.

First, I disconnected all wires from the orange plug all the way to the horn button. Turned ignition on and horn sounded. Keep in mind the only connection still plugged in was the "airbag" bypass. Red connectors, brown and brown/white wires.
Totally frustrated, I clipped the remaining wires mentioned above and turned the key. No horn blast.
Soooooo, I swapped the leads, grounds and resistors, tied everything up and turned the key again. No horn sound. pushed the born button (center section of steering wheel propped up since wheel was still off as well as steering column cover were still not put back on until problem was fixed) Horn worked.

Could it be that out of the hundreds of people who have done this mod, mine is the only car that is different? Unlikely. Is my car possessed? Possibly.

I made note of all the connections, then proceeded to make more permanent, tucked, bolted and re-assembled everything and turned the key one more time. no horn blast. pressed the horn button.
NO HORN BLAST!
(this is getting out of hand)

Out of desperation and possibly frustration, I grabbed the wheel and turned vigorously thinking maybe the L shape lost it's contact somehow, then rapidly tapped the horn button with gusto.....At this time, the gremlins in the car decided to look the other way and the horn sounded...

Now I am usually known to take things a bit too far sometimes and in this case, decided if my hunch was correct- Oil or something preventing a good contact being on the L shape brass, I turned the wheel quickly lock to lock with the ignition on...

As I did, the horn sounded on it's own but in very short bursts and rarely at full blast.

There is no way I am going to drive the car with the horn moaning with every turn...so I promptly gathered my tools out of the car, shut the door, bonnet and proceeded to go get myself a stiff drink.

Don't tell anyone, but I really do miss my S2000.

So... apparently I still have some wiring issues. I have not started the car since disconnecting the battery yet, and have no idea of the airbag bypass status. (yes, light was on in the gauge as well as the " ! " light in the console.)

sawitt

I feel your pain, believe me. I'm having my own battles with my convertible top. When you do get your #$%&*@#$ horn working, you'll have earned another good, stiff drink. Good luck with it.

Resident Sicko

Wondering if a low battery charge level would contribute.. Tried to fire up the car for the first time in several weeks and have drained the battery from all the modification checks...(LED bulbs, headlights, fog lights, tail lights, etc.)
Put on trickle charger and will see.

Resident Sicko

Ended up doing this instead. Better to focus attention on something else for a while to sort out the issues of the first project sometimes.

mcipseric

I feel your pain. After the car gets off the jack stands, I think you will have to go to a trusted tech to get the airbag light turned off so your passenger airbag will still work. Might as well have them check out the horn issue. Sometimes an extra set of eyes will do the trick.
Might be the best $100 spent for your sanity.

Resident Sicko

Great advice although some would debate that I lost that a LONG time ago..

porschemeister

I did this some time ago on my 964 using the bridge as described in the following instructions. I believe I got them from this site 4 or 5 years ago.

Hope this helps...

Porsche Airbag removal:

Let's start with a few disclaimers:
- Disabling the airbag is not recommended by the manufacturer
- The Momo adapter hub #7004 is not a perfect fit with the stock column collar. You must modify the hub collars to complete this installation (see below).
- Disconnecting the airbag may activate the warning lights and require a trip to your nearest Porsche dealership to reset (usually a five minute job with the Bosch Hammer).

If still interested, keep reading.

Parts & tools required:

- Momo wheel
- Momo hub adapter 7004
- Porsche airbag tester 000.721.951.60 (not 9516/1) not needed see below:

Better solution: Airbag bridge plug 928.612.220.00
The 928.612.220.00 number plug bridges the circuitry disconnects both airbags.
The location of the plug is shown on Sheet 15 of the 911 Carrera 2/4 Model '92 wiring diagrams in the factory manual.
It bridges terminals 3 and 4 in the T6 connector in the forward section of the center console, access door on passenger side. It is held with an orange clip. With this plug installed the warning lights do not come on.

Remove the following:
The Diagnositc Unit including the airbag wiring harness: -2 pounds, L +R crash sensors approx. -0.5 pounds , Driver + Passenger Airbags -11 pounds.

- Porsche horn contact 964.652.104.00
- Male and female wiring contacts. The spade type often used to connect audio speakers.
- Torque wrench
- Torx T30 screwdriver socket
- ½" rachet driver with 5" socket extension
- 24mm socket (15/16" might be a better fit if you can find one)
- Phillips head screwdriver

Step 1. To begin, disconnect the battery ground and wait at least 20 minutes before attempting this installation to prevent accidental airbag ignition.

Step 2. Loosen the two screws located at 9 and 3 o'clock on the back side of the steering wheel using the T30 socket. These screw hold the bag on to the wheel and once loosened, will allow you to "lift" the airbag right off the wheel. It will be connected by a wire from the column which you can easily unplug.

Step 3. To get the wheel off the column, I used a 24mm socket BUT it was a little loose--it works, but it's not a precise fit. Loosen the bolt, remove the accompanying washer, unplug the horn contact wire and remove the wheel from the steering post.

Note: You will want to mark the top dead center location (TDC) of the steering post to facilitate installation of the new wheel.

Step 4. The column collar requires the removal of 6 phillips head screws, four on the face and two on the sides. It's tricky getting the bottom half off the column, especially if you have a cruise control stalk, so be gentle as you ease it off.

Step 5. The final piece to remove is the horn contact plate. It's a circular piece made of plastic and a flat copper ring. Basically, it allows you to turn the wheel without tangling or unplugging the wires in the hub. It's two more screws.

Step 6. Now, gently pull the wiring attached to the contact plate out from the dash. The horn and airbag wiring is sheathed in a rubber tube. Sliding it up will reveal the two plugs connected to the contact plate which you can disconnect to keep the plate intact. You will need to clip the airbag wire on the front of the plate to attach the 9516 tester.

Step 7. Now you need to install the Factory horn contact 964.652.104.00 to the stalk assembly. Do you see the curved metallic part surrounding the center? That piece passes current and makes contact with the metallic bottom of the Momo hub; without this contact, the horn will not work.

Courtesy of Dave Gordon:


Note: The 7004 hub is the correct part but the diameter is actually just a little big. The solution is to sand off some material from the collar halves to enlarge the opening---CAREFULLY-- so that they fit around the adapter. I used the sandpaper sheet wrapped around a coke can trick to trim it back.

Step 8. Install the hub and secure with washer and nut; torque to 32.5 ft lbs. Make sure to seat the hub with one of the wheel mounting holes lined up with the post's TDC mark. Again, the forward edge of the column covers should straddle the outside of the adapter.

Step 9. Airbag wiring. You'll need to splice the airbag lead to the wire coming out of the dash. The airbag tester is a 2" x 1/2" wafer housed in a plastic box. Lose the box and find a secure place to locate the tester behind the steering column.

Step 10. Horn wiring. (Sorry, I'm a little fuzzy, here) You will need to mount a spade type contact to the back of the horn if two are not present. There's a small screw hole already there and you'll probably want to take the horn to your hardware store to find the right size screw. The screw makes contact with the coil spring under the horn button when depressed. Momo supplies a wire which attaches to the male contact located in the hub (ground) and the horn button. Route the lead (from behind the dash?) and ground wires through the hub and unattached wheel center, connect them to the horn button and press it into place along with the mounting ring.



Step 11. Mount the wheel to the hub with the six screws supplied (I think it's 5 ft lbs), reconnect the battery and fire it up. Check the horn and drive around the block to ensure the steering hub was properly centered.

Resident Sicko

Thank you.
I made reference to these posts prior to install, but you reminded me to bypass the 3 ohm plus trip to dealership and just install the airbag bridge plug.

I am ready for round 2 of trouble shooting. I suspect the following:

With bridge plug installed, I will for the final time confirm that my 98 C2S is in fact a "one of a kind" that came from the factory with opposite colored wires and connectors for the airbag and horn in steering column....or the "horn" will simply not work....RIGHT?

If so, than I still have the "sounding off when steering wheel is turned" issue which could be another bucket of monkeys and will require some time to discover the cause. I suspect the addition of female connector in circut box in front of steering column plate to be faulty...this is the connection used to power the "L shape Porsche Horn Contact".

(Intert famous Buzz Lightyear catch phrase here)

Resident Sicko

Checked Porsche wiring diagram and let it be known for all who care:

Brown/brown&white wires are in fact HORN (red connection)
Green&red/Green&blue wires are in fact driver's side airbag. (Orange connection)

(At least on the 993)

Resident Sicko

Okay.

This is the plug I was sold from Pelican. (Airbag bypass) Nothing more than a wire with two male connector pins in a harness.


This where the Airbag control unit is. (sensors and leads from actual airbags)
With the OE plug pulled out.


This is the plug itself...nitice how the pins are smaller? Notice how the shape is different?

Do I have the wrong plug? (Read on here that the part I have (p/n 928.612.220.00 is the same as p/n 964.612.220.00 and even confirmed with Pelican prior to ordering) I suspect it is not due to pin size.

Resident Sicko

Findings confirmed...928 part will NOT work. Pins are too big and does not line up.

Thanks to all that helped. I think this chapter is closed. Resistors in place for driver's airbag, passenger should still be functional. Steering wheel mounted and horn is powered. Just need to figure out the "honking while turning" issue...maybe that extra ground is not needed, or the horn contact to the MoMo adapter needs some use to get it to sit right...

Electronics blow.

Resident Sicko

FIXED. Thanks to all that provided guidance.

Everythying finally works as it should.