Really excited just taken ownership of a 1992 build registered Jan 93 UK 928 GTS in Gaurds Red with 70k miles on the clock . Generally in very good condition - had a PPI which identified a number of fluid leaks that need sorting and air con not operating which may or may not be simply a re gas . Anyway having studied the manual I cannot find out what a switch by the drivers seat does . Simple on off switch that has a flashing LED by the centre armrest when switched one way . It’s not the alarm as the OE system and immobiliser still in situ with LED by the ashtray . Any thoughts would be appreciated . Many thanks

 

You might have to trace the wires. To my knowledge that switch and LED are not stock.

 

Do the seats get warm?

Here's my self-install of heat pads

 

I have the same switch and light in my car, its stock, my car had factory alarm but is now disconnected, i asked on forum before here is the best answer:

"There is / should be an insert pasted page 10 or 11 of your Driver's Manual on this. It is associated with the Alarm. If this has been deleted the switch probably will not do anything. This 'Vent' switch allows the auto closing of the roof and the windows to be cancelled so they can be left open with the vehicle locked."

 

PS i have now connected that switch to do the "kickdown mod" it works great and kept it looking stock

 

no seat heating

 

Thanks - no inserted pages in my manual although there are also a few pages missing . I still have the factory immobiliser ( think it was fitted by Porsche Uk) that has two sellotaped ‘keys’ which have a mind of their own as to work or not . I did find if I keep the door key in the lock position the windows, If open , close so will flick the switch and see if that stops that process . I also have two non operating fobs as well as the immobiliser keys which I assumed were for central locking the car remotely . It is an interesting learning curve but one I’m enjoying and love the car .

 

The alarm system seems to have been regional and had year changes, so it hard to find correct documents on operation / troubleshooting, hence most get removed so good yous is still live, enjoy the new wheels.

 

I also own a '92 GTS built for the Canadian market, no switch no light. Wonder if it was a option for cars sold in Europe/UK?

North American cars also do not have the light switch in the same location although some cars that were exported to Japan that Ive saw have this same switch.

 

Its not Porsche stock, nor is the alarm LED - though it may be a dealer install before initial delivery - that was quite common on 928's in the UK market especially.

Do you also have the stock alarm - flashing LED lock stems? and the longer key?

Alan

 

Thanks for all the responses .


I have a barrel type receiver under the dash to rhs of steering wheel and I have the keys/fobs as in the picture . The led for the alarm is by the ashtray . Neither of the larger fobs seem to work - assume these are for central locking . The smaller Immobiliser fobs work when they feel like it - slightly frustrating .

 

You have the remote central locking and immobiliser installed by UK dealers (looks like PA100 single button). The actual modules were provided by Hamilton and Palmer who are still trading (though more involved in commercial security these days) and even selling new fobs, immobiliser fobs and remote modules!

You should find the black plastic H&P boxes behind the CE cover — one may be tucked behind centre console carpeting. One module provides remote lock/unlock and indicator acknowledge flash (2 flashes for lock, one for unlock), the other interfaces with window/sunroof control box under passenger seat to provide window close on locking (if that rocker switch is in 'non-vent' position). It all works in parallel with the 928.618.260.00 alarm unit fitted to all Porsches MY91 onwards. It's fully documented in the 1991 Service Info. I've just refurbed my remote circuit board with new relay and new transistors. It's now all working but to be honest I've still not completely determined how the single channel H&P system interfaces with the factory system which has separate inputs for lock/unlock!. If I have any other problems I'll just go for generic solution(see below)

If the H&P units no longer work it's very easy to find generic remote boxes which do the same thing, and interface very simply with the factory alarm system. There's also a very helpful guy (Tore Bergvill, who posts here occasionally on alarm matters) who runs https://www.bergvillfx.com that provides dedicated remote lock/unlock with full instructions for how to connect to the factory alarm if you want a plug&play solution. The generic units are much cheaper but require a little more knowledge about which leads to patch into from the factory alarm connectors.

I only had one remote fob, but a 'cloning' fob picked up for a few £ on eBay was able to learn the code transmitted by the original fob so I now have spare. It's not a sophisticated rolling code system, and uses the standard 433.92MHz frequency as per European standard.

 

The Porsche alarm system is based only on the key - just a regular key not electronic. The longer keys are alarm keys - yours are indeed the longer keys.

So the fob & immobilizer you show is for an aftermarket system - likely as noted before - installed by dealer before initial delivery. I'm not sure why they did this a lot in the UK since the stock alarm is really quite adequate and very reliable (at least until someone screws with it or the equipment it monitors). If they just did it to add Keyless Entry there are many options to achieve this simply with inexpensive & better more modern systems if yours is non-functional.

In the USA all GTS cars were delivered with (only) factory alarms.

Alan

 

I have a late late 1992 - 93 MY GTS 5spd which was THE928S initially. It has exactly the same alarm system as yours, whcih is absolutely pants I have to say as it kills the battery if left for more than 3 weeks. In contrast my LHD 1990 GT - ex German car - only had the factory alarm, and that would last months on end. Really need to get my *** in gear and drop in on Hamilton and Palmer and have them remove their alarm from my GTS.

 

Going by the letter from Porsche dealer in my file, they added the immobiliser in UK dealerships to match UK insurance requirements. The remote entry (from same supplier Hamilton & Palmer) as you said provided remote lock/unlock only with no alarm function, though they also usually added a module for cabin movement sensor (sensors at corners of rear hatch, monitoring box under rear of spare wheel perspex cover) as the factory alarm had capacity for extra sensor inputs.