Steering wheel swop

[ronbonner]

I just finished a 4 spoke to a 3 spoke steering wheel swop and I thought I had prepared myself well.

I downloaded the guide found on this forum which firstly suggested I disconnect the neg side of the battery. That set off the alarm!!

Reconnected to shut it off and luckily I had the tools to undo the Torx screws without having to turn the wheel so I left the keys out and did the swop. New wheel looks great but on turning the key the airbag light stays on.

Oh! and the PCM 1 won't recognise the code number.

Help please

Ron

[Loren]

If your air bag light is on then the only way to turn it off is with a PST2 or PIWIS tester - at an OPC or shop. If you take it to an OPC then they can check your PCM1 serial number against the code you are entering and get you the right one if it is not correct.

[Tool Pants]

For insurance reasons UK cars have an alarm siren and tilt sensor. We do not have this in the US. We just have an alarm horn, which is the round silver thing next to the battery. Your car has the alarm horn and siren. The siren has a built in rechargeable battery for power. If you try to disconnect the battery the alarm siren will go off.

You need to turn the key on first before disconnecting the battery. Then the alarm siren will not go off.

[ronbonner]

Thanks Guys,

Code was sourced for me by OPC when Clutch was replaced 12 months ago.

I called them to check the code and I am putting in the correct code in according to the Porsche records. So a real mystery and a bummer with no music

They will reset the Airbag light when I can get it to them. Any ideas on why it came on in the first place?

Thanks for the heads up on the battery disconection and the ignition key, wish I had known that first and so do my neighbours!!!!!!!

Ron

[Tool Pants]

If the battery is hooked up and the key is in the on position and if you disconnect an air bag, then you will get the light. Since you said the key was out of the ignition I have no clue why the light went on. Hope you remembered to hook up the new air bag.

It takes 2 minutes for your OPC to turn off the light. Just play dumb when you bring it in

[ronbonner]

Yeah, I had the airbag off a second time to check the connections so I am confident that the connections are all on.

I do plan to keep the fact that the wheel had just been changed to myself!

Thanks

Ron

[0586slb]

Most airbag circuits have a standing time you have to wait after the power is disconnected. This is to allow the energy in the capacitors in the airbag module to dissipate and render the system safe to work on. The capacitors are in the firing circuit to provide the energy to deploy the airbag, if for instance, the battery connections are disturbed or a part of your body hits and damages the ignition switch during an impact. This standing time is generally 10 minutes, 20 mins on some - so I usually wait half an hour!! If you have removed the airbag in this time, the module can set a code and the warning light will illuminate on switch on.

Once the airbag is out of its storage crate or the vehicle, place cushion side up - this way if it goes off with static it does not become a 200mph projectile.

! ! * WARNING * ! !

NEVER TEST THE RESISTANCE OF THE AIRBAG.

Just let the control module tell you if its bad. There's enough energy from a multimeter on resistance range to deploy the bag.

Edited May 6, 2005 by 0586slb

[Tool Pants]

I have seen this 30 minute rule of thumb a few times. I have never followed it. I do not know if it applies to a 996/986. Never seen it in the 986 shop manual.

I have done many steering wheel/air bag removals over the years. For the 4 to 3 spoke swap, or for the OBC retrofit.

My late friend Dave with a 1998 Boxster went on a group drive. Then the group stopped for lunch. Dave was turning in his leased car in a few days. So while we were all parked outside the restaurant I removed his 3 spoke and put his original 4 spoke back on. Took 10 minutes. Then we were in the restaurant with the rest of the group ordering lunch, with Dave's 3 spoke at the table.

I then put Dave's 3 spoke in Doc Wong's 1997 Boxster which had a 4 spoke.

The second after the negative battery cable is removed I pull the wheel. Never had an air bag light.